Hoplite
Peltast
Foederatus
Phalangitai
Legatus
Zeugitai
Onager

These are ones I added to Escalation Classes:

Scout - Shinobi(?)
RandomNickNames="Bandit"
RandomNickNames="Blitz"
RandomNickNames="Cajun"
RandomNickNames="Clutch"
RandomNickNames="Cobra"
RandomNickNames="Cougar"
RandomNickNames="Coyote"
RandomNickNames="Dagger"
RandomNickNames="Dancer"
RandomNickNames="Dash"
RandomNickNames="Dasher"
RandomNickNames="Dart"
RandomNickNames="Desperado"
RandomNickNames="Devil Dog"
RandomNickNames="Dodger"
RandomNickNames="Dragon"
RandomNickNames="Fencer"
RandomNickNames="Firefly"
RandomNickNames="Flash"
RandomNickNames="Flipper"
RandomNickNames="Furball"
RandomNickNames="Ghost"
RandomNickNames="Gopher"
RandomNickNames="Hawk"
RandomNickNames="Joker"
RandomNickNames="Juice"
RandomNickNames="Leopard"
RandomNickNames="Lightfoot"
RandomNickNames="Lightning"
RandomNickNames="Loco"
RandomNickNames="Mace"
RandomNickNames="Mercury"
RandomNickNames="Midnight"
RandomNickNames="Mongoose"
RandomNickNames="Mustang"
RandomNickNames="Neutron"
RandomNickNames="Nitro"
RandomNickNames="Northstar"
RandomNickNames="Painter"
RandomNickNames="Panther"
RandomNickNames="Pasha"
RandomNickNames="Poacher"
RandomNickNames="Puma"
RandomNickNames="Python"
RandomNickNames="Rascal"
RandomNickNames="Rattler"
RandomNickNames="Razor"
RandomNickNames="Ripper"
RandomNickNames="Rogue"
RandomNickNames="Royal"
RandomNickNames="Sandstorm"
RandomNickNames="Shadow"
RandomNickNames="Shady"
RandomNickNames="Slipstream"
RandomNickNames="Snake"
RandomNickNames="Snake Eyes"
RandomNickNames="Solo"
RandomNickNames="Spacebar"
RandomNickNames="Specter"
RandomNickNames="Spider"
RandomNickNames="Splinter"
RandomNickNames="Stalker"
RandomNickNames="Sticks"
RandomNickNames="Stretch"
RandomNickNames="Sweetfoot"
RandomNickNames="Talon"
RandomNickNames="Teflon"
RandomNickNames="Trips"
RandomNickNames="Turbo"
RandomNickNames="Undertaker"
RandomNickNames="Vortex"
RandomNickNames="Whiz"
RandomNickNames="Wildcat"
RandomNickNames="Zipper"

RandomNickNames_Male="Bender"
RandomNickNames_Male="Slim"
RandomNickNames_Male="Jockey"
RandomNickNames_Male="Sandman"

RandomNickNames_Female="Panther"
RandomNickNames_Female="Siren"
RandomNickNames_Female="Sparkplug"
RandomNickNames_Female="Spitfire"

Rocketeer - Technical(?)
RandomNickNames="Annihilator"
RandomNickNames="Backblast"
RandomNickNames="Barbecue"
RandomNickNames="Bazooka"
RandomNickNames="Bomber"
RandomNickNames="Boom Boom"
RandomNickNames="Buster"
RandomNickNames="Charbroil"
RandomNickNames="Claymore"
RandomNickNames="Countdown"
RandomNickNames="Cyclone"
RandomNickNames="Danger"
RandomNickNames="Defcon"
RandomNickNames="Demo"
RandomNickNames="Demolisher"
RandomNickNames="Diesel"
RandomNickNames="Downtown"
RandomNickNames="Dozer"
RandomNickNames="Dreadnought"
RandomNickNames="Dynamite"
RandomNickNames="Fireball"
RandomNickNames="Grand Slam"
RandomNickNames="Hammer"
RandomNickNames="Hardtop"
RandomNickNames="Hellfire"
RandomNickNames="Hightower"
RandomNickNames="Incinerator"
RandomNickNames="Junkyard"
RandomNickNames="Juggernaut"
RandomNickNames="Knockdown"
RandomNickNames="Kong"
RandomNickNames="Landslide"
RandomNickNames="Magma"
RandomNickNames="Meltdown"
RandomNickNames="Neutron"
RandomNickNames="Nova"
RandomNickNames="Nuke"
RandomNickNames="Payload"
RandomNickNames="Pulsewave"
RandomNickNames="Pyro"
RandomNickNames="Quake"
RandomNickNames="Redzone"
RandomNickNames="Rhino"
RandomNickNames="Rockslide"
RandomNickNames="Rumbler"
RandomNickNames="Salvo"
RandomNickNames="Scorch"
RandomNickNames="Scrap-Iron"
RandomNickNames="Shockwave"
RandomNickNames="Short Fuse"
RandomNickNames="Slab"
RandomNickNames="Sledge"
RandomNickNames="Smash"
RandomNickNames="Smokey"
RandomNickNames="Tank"
RandomNickNames="Tectonic"
RandomNickNames="Thumper"
RandomNickNames="Thunder"
RandomNickNames="Tiny"
RandomNickNames="Titan"
RandomNickNames="Torch"
RandomNickNames="Torpedo"
RandomNickNames="Volcano"
RandomNickNames="Wildchild"
RandomNickNames="Wreckage"

RandomNickNames_Male="Nero"

RandomNickNames_Female="Auntie"
RandomNickNames_Female="Firebug"

Gunner
RandomNickNames="Anvil"
RandomNickNames="Atlas"
RandomNickNames="Axle"
RandomNickNames="Backfire"
RandomNickNames="Baja"
RandomNickNames="Barricade"
RandomNickNames="Bearcat"
RandomNickNames="Blocker"
RandomNickNames="Brutal"
RandomNickNames="Brick"
RandomNickNames="Bull Rush"
RandomNickNames="Castle"
RandomNickNames="Chainsaw"
RandomNickNames="Crossfire"
RandomNickNames="Decimator"
RandomNickNames="Dynamo"
RandomNickNames="Flattop"
RandomNickNames="Flood"
RandomNickNames="Flounder"
RandomNickNames="Freight-Train"
RandomNickNames="Fridge"
RandomNickNames="Gameshow"
RandomNickNames="Gladiator"
RandomNickNames="Gonzo"
RandomNickNames="Hawker"
RandomNickNames="Heavy Duty"
RandomNickNames="Hotrod"
RandomNickNames="Hurricane"
RandomNickNames="Iron Anvil"
RandomNickNames="Juggernaut"
RandomNickNames="Kinetic"
RandomNickNames="Knockout"
RandomNickNames="Kozmo"
RandomNickNames="Lunchbox"
RandomNickNames="Mangler"
RandomNickNames="Meatgrinder"
RandomNickNames="Meathook"
RandomNickNames="Moose"
RandomNickNames="Nanook"
RandomNickNames="Nugget"
RandomNickNames="Ogre"
RandomNickNames="Overkill"
RandomNickNames="Pancake"
RandomNickNames="Panzer"
RandomNickNames="Phalanx"
RandomNickNames="Piston"
RandomNickNames="Rampart"
RandomNickNames="Rhino"
RandomNickNames="Roadblock"
RandomNickNames="Slinger"
RandomNickNames="Sparrow"
RandomNickNames="Spike"
RandomNickNames="Stalwart"
RandomNickNames="Steamroller"
RandomNickNames="T-bone"
RandomNickNames="Tank"
RandomNickNames="Tempest"
RandomNickNames="Volley"
RandomNickNames="Warden"
RandomNickNames="Warhound"
RandomNickNames="Yogi"
RandomNickNames="Zarfer"

RandomNicknames_Male="Barbarian"
RandomNicknames_Male="Boss Man"
RandomNickNames_Male="Chuckles"
RandomNickNames_Male="Dingus"
RandomNickNames_Male="Knuckles"
RandomNickNames_Male="Maniac"
RandomNickNames_Male="Meathead"
RandomNickNames_Male="Odin"
RandomNickNames_Male="Papa Bear"
RandomNickNames_Male="Walrus"
RandomNickNames_Male="Wildman"

RandomNicknames_Female="Boss Lady"
RandomNickNames_Female="Bubbles"
RandomNickNames_Female="Deep Six"
RandomNicknames_Female="Domino"
RandomNickNames_Female="Freya"
RandomNickNames_Female="Gadget"
RandomNickNames_Female="Giggles"
RandomNickNames_Female="Mama Bear"
RandomNickNames_Female="Mango"
RandomNickNames_Female="Pepper"

Lucabration's Infantry Class - Ranger
RandomNickNames="Arcade"
RandomNickNames="Blaster"
RandomNickNames="Blitz"
RandomNickNames="Blowtorch"
RandomNickNames="Bronco"
RandomNickNames="Buck"
RandomNickNames="Buckeye"
RandomNickNames="Cannonball"
RandomNickNames="Casino"
RandomNickNames="Clash"
RandomNickNames="Claymore"
RandomNickNames="Cloudburst"
RandomNickNames="Cobalt"
RandomNickNames="Deep-six"
RandomNickNames="Digger"
RandomNickNames="Dinger"
RandomNickNames="Dogfight"
RandomNickNames="Dropzone"
RandomNickNames="Enforcer"
RandomNickNames="Excalibur"
RandomNickNames="Frosty"
RandomNickNames="Gator"
RandomNickNames="Grunt"
RandomNickNames="Gunpowder"
RandomNickNames="Hardball"
RandomNickNames="Hardcore"
RandomNickNames="Havoc"
RandomNickNames="Hazard"
RandomNickNames="Headhunter"
RandomNickNames="Howler"
RandomNickNames="Jaybird"
RandomNickNames="Jayhawk"
RandomNickNames="Judge"
RandomNickNames="Marlin"
RandomNickNames="Mace"
RandomNickNames="Magnum"
RandomNickNames="Manslaughter"
RandomNickNames="Mustang"
RandomNickNames="Painter"
RandomNickNames="Paladin"
RandomNickNames="Pinto"
RandomNickNames="Raider"
RandomNickNames="Rascal"
RandomNickNames="Rocky"
RandomNickNames="Saber"
RandomNickNames="Scooter"
RandomNickNames="Scorpion"
RandomNickNames="Shard"
RandomNickNames="Skeeter"
RandomNickNames="Skids"
RandomNickNames="Spike"
RandomNickNames="Steel"
RandomNickNames="Stretch"
RandomNickNames="Templar"
RandomNickNames="Thumper"
RandomNickNames="Trojan"
RandomNickNames="Warden"
RandomNickNames="Warlord"
RandomNickNames="Warpath"
RandomNickNames="Zulu"

RandomNickNames_Male="Duke"
RandomNickNames_Male="Dusty"
RandomNickNames_Male="Dutch"
RandomNickNames_Male="Husker"
RandomNickNames_Male="Pops"
RandomNickNames_Male="Rocky"
RandomNickNames_Male="Slick"
RandomNickNames_Male="Stallion"
RandomNickNames_Male="Wolfman"

RandomNickNames_Female="Athena"
RandomNickNames_Female="Duchess"
RandomNickNames_Female="Goodnight"
RandomNicknames_Female="Iron Maiden"
RandomNickNames_Female="Medusa"
RandomNicknames_Female="Shieldmaiden"
RandomNickNames_Female="Sugar"
RandomNickNames_Female="Valkyrie"

Lucabration's Sniper Class - Sharpshooter
RandomNickNames="Adept"
RandomNickNames="Aero"
RandomNickNames="Alpha"
RandomNickNames="Alpine"
RandomNickNames="Altitude"
RandomNickNames="Ambush"
RandomNickNames="Archer"
RandomNickNames="Assassin"
RandomNickNames="Blackout"
RandomNickNames="Blink"
RandomNickNames="Bonus"
RandomNickNames="Boxcars"
RandomNickNames="Bullseye"
RandomNickNames="Buzzer"
RandomNickNames="Camo"
RandomNickNames="Carcass"
RandomNickNames="Carnivore"
RandomNickNames="Chamber"
RandomNickNames="Chameleon"
RandomNickNames="Chance"
RandomNickNames="Changeling"
RandomNickNames="Checkmate"
RandomNickNames="Cloak"
RandomNickNames="Copperhead"
RandomNickNames="Crackerjack"
RandomNickNames="Creeper"
RandomNickNames="Critical"
RandomNickNames="Crosshair"
RandomNickNames="Cyborg"
RandomNickNames="Deadbolt"
RandomNickNames="Dice"
RandomNickNames="Ding"
RandomNickNames="Drifter"
RandomNickNames="Eagle"
RandomNickNames="Echo"
RandomNickNames="Enigma"
RandomNickNames="Freakshow"
RandomNickNames="Gambler"
RandomNickNames="Garrote"
RandomNickNames="Ghost"
RandomNickNames="Harpoon"
RandomNickNames="Headshot"
RandomNickNames="Hex"
RandomNickNames="Hijack"
RandomNickNames="Hit & Run"
RandomNickNames="Hollow Point"
RandomNickNames="Hunter"
RandomNickNames="Husk"
RandomNickNames="Ice"
RandomNickNames="Imp"
RandomNickNames="Ion"
RandomNickNames="Kaput"
RandomNickNames="Killing Spree"
RandomNickNames="Laser"
RandomNickNames="Legend"
RandomNickNames="Lockdown"
RandomNickNames="Longbow"
RandomNickNames="Longshot"
RandomNickNames="Lucky"
RandomNickNames="Lurker"
RandomNickNames="Midnight"
RandomNickNames="Migraine"
RandomNickNames="Mimic"
RandomNickNames="Miracle"
RandomNickNames="Mirage"
RandomNickNames="Nightcrawler"
RandomNickNames="Nix"
RandomNickNames="Nocturne"
RandomNickNames="Omega"
RandomNickNames="Panic"
RandomNickNames="Pinpoint"
RandomNickNames="Poison"
RandomNickNames="Polaris"
RandomNickNames="Predator"
RandomNickNames="Psyche-Out"
RandomNickNames="Quicksilver"
RandomNickNames="Rampage"
RandomNickNames="Ranger"
RandomNickNames="Reaper"
RandomNickNames="Rebel"
RandomNickNames="Recoil"
RandomNickNames="Redeye"
RandomNickNames="Rockstar"
RandomNickNames="Scorpion"
RandomNickNames="Serpent"
RandomNickNames="Shadow"
RandomNickNames="Shooter"
RandomNickNames="Sickle"
RandomNickNames="Sizzler"
RandomNickNames="Skull-Buster"
RandomNickNames="Skystriker"
RandomNickNames="Slayer"
RandomNickNames="Slick"
RandomNickNames="Slider"
RandomNickNames="Smokes"
RandomNickNames="Snap"
RandomNickNames="Sneak"
RandomNickNames="Snowstorm"
RandomNickNames="Solo"
RandomNickNames="Spearhead"
RandomNickNames="Specter"
RandomNickNames="Spider"
RandomNickNames="Spirit"
RandomNickNames="Splat"
RandomNickNames="Stalker"
RandomNickNames="Stiletto"
RandomNickNames="Surefire"
RandomNickNames="Surge"
RandomNickNames="Syndrome"
RandomNickNames="Taser"
RandomNickNames="Thunder"
RandomNickNames="Tiger Claw"
RandomNickNames="Topside"
RandomNickNames="Tracker"
RandomNickNames="Trapdoor"
RandomNickNames="Trigger"
RandomNickNames="Tripwire"
RandomNickNames="Twitch"
RandomNickNames="Two-time"
RandomNickNames="Updraft"
RandomNickNames="Vampire"
RandomNickNames="Vanisher"
RandomNickNames="Vanguard"
RandomNickNames="Vapor"
RandomNickNames="Venom"
RandomNickNames="Viper"
RandomNickNames="Voodoo"
RandomNickNames="Wasted"
RandomNickNames="Waxer"
RandomNickNames="Whiteout"
RandomNickNames="Wildcard"
RandomNickNames="Fatality"
RandomNickNames="Windchill"
RandomNickNames="Wing"
RandomNickNames="Wraith"
RandomNickNames="Zap"
RandomNickNames="Zero"
RandomNickNames="Zing"

RandomNickNames_Male="Apollo"
RandomNickNames_Male="Godfather"
RandomNickNames_Male="Houdini"
RandomNickNames_Male="Icarus"
RandomNickNames_Male="Pimpin'"
RandomNickNames_Male="Salesman"
RandomNickNames_Male="Sandman"
RandomNickNames_Male="Taxman"
RandomNickNames_Male="Warlock"
RandomNickNames_Male="Wild Bill"

RandomNickNames_Female="Finesse"

Think I got most of these from the LW 1 "Enhanced Soldier Nicknames - Long War" mod - http://www.nexusmods.com/xcom/mods/521/

I think a lot of those are already in here, but I've added them anyway (I sort and deduplicate prior to release). Thanks!

De-duplicating? Really good idea! And no worries. Hope a couple are new at least.

Persona

Try looking up reporting names sometimes. NATO ones for aircraft/helicopters and the like are pretty good.

Also, old British Army radio signs. Starlight for medical, Ironside for armour, etc.

Hey there, setting up using these nicknames with Perk Pack. Spotted a few typos doing that, below are corrected versions (American English spellings):

Psi
+RandomNickNames="Djinn"
+RandomNicknames_Male="Poseidon"

Sharpshooter
+RandomNickNames="Garrote"
+RandomNickNames="Iceberg"
+RandomNickNames="Judgment"
+RandomNickNames="Sepulcher"

Gunner
+RandomNickNames="Banzai"
+RandomNickNames="Mjolnir"
+RandomNickNames="Sulfur"

Ranger
+RandomNickNames="Geronimo"
+RandomNickNames="Guerrilla"

Shinobi
+RandomNickNames="Geronimo"
+RandomNickNames="Guerrilla"

Specialist
+RandomNicknames_Female="Empress"

Grenadier
+RandomNickNames="Mjolnir"

Assault
+RandomNickNames="Odyssey" [?] currently "Odysee"
+RandomNicknames_Female="Empress"

Hi, so in modifying the nicknames for Perk Pack I... did a little bit more.

Consolidated the nicknames so that each nickname is only used for once by a single class
Added in a few new ones
Corrected some typos
Set some nicknames to male- / female-specific where appropriate.
Compared against the built-in nickname lists for Long War 2 (which are the same ones used for Perk Pack) and ensured that all nicknames are new and unique. Although with the way I understand INI files working I don't think that was strictly necessary.
I've tried, as much as possible, to match the nicknames to the theme of the character class; although I haven't done an exhaustive pass through the entire set, rather assigned duplicates to the most appropriate class whilst trying to keep the number for each somewhat balanced.

Counts of new, unique nicknames:
SPARK - 79
Psi Op - 192
LW Assault - 152
LW Grenadier - 122
LW Gunner - 133
LW Ranger - 154
LW Sharpshooter - 292
LW Shinobi - 154
LW Specialist - 185
LW Technical - 125

Quite a large wodge of text so it's on Pastebin: https://pastebin.com/n4yihqt0

Woah, thanks for.. basically doing my work for me.
If it's cool with you, I'll push your version to the master in a bit. Sound good?

Absolutely, double-check it as I've just done this as a paper exercise rather than exhaustively testing it. I'm trying to get things in shape for a new campaign and thought I'd share what I'd done with this.

Dagda
Nuada
Ankou

+RandomNickNames="Destiny"
+RandomNickNames="Logic"
+RandomNickNames="Telemetry"
+RandomNickNames="Comms"
+RandomNickNames="Redacted"
+RandomNickNames="Classified"

Chinese Deities
+RandomNickNames="Erh-Lang"
+RandomNickNames="I-ti"
+RandomNickNames="Kuan Ti"
+RandomNickNames="Lao-Tein-Yeh"
+RandomNickNames="Feng-Po"
+RandomNickNames="Meng-Po-Niang"
+RandomNickNames="Chang O"
+RandomNickNames="Lei-Hung"

Celtic Dieities
+RandomNickNames="Nemain"
+RandomNickNames="Mebd"
+RandomNickNames="Mider"
+RandomNickNames="Morrigan"
+RandomNickNames="Maeve"
+RandomNickNames="Giobhniu"
+RandomNickNames="Camalus"
+RandomNickNames="Airmid"

Japanese Dieties
+RandomNickNames="Ho-Masubi"
+RandomNickNames="Nai-No-Kami"
+RandomNickNames="O-Kuni-Nushi"
+RandomNickNames="Take-Mikazuchi"
+RandomNickNames="Bishamon"
+RandomNickNames="Hiruko"
+RandomNickNames="Sarutahiko Ohkami"
+RandomNickNames="Amaterasu"