< We need mobility >=8 to spawn at these positions.
Few things to note:

• Mk27 weighs nothing even with a suppressor. You can always equip it.
  
• However, don't rely on pistols unless you invested some doctrine points.
  
• Sights I use: Holo-sight, 1-6x LPVO, LR 3.5-10x, LR 3-18x
  
• Suppressor will extend attack type further, yet also increase weight and length

Assaults have lightweight main weapons, grant us various builds.

Back pack: slap charges or grenades.
Suppressor is not recommended for room clearing.
+Good at clearing rooms and apartments
-Limited mid-range capability


Any item for back pack except for rocket.
+Breaching charge
+Still good protection for room clearing
-Limited mid-range capability


Back pack: slap charges or grenades.
Suppressor is recommended for better attack types.
+Better mid range shooting
-Slightly slower in CQC than holosight


Back pack: slap charges or grenades.
Same goes for URG-I.
+All-around, all range
-Slightly slower in CQC than holosight
-Mk27 is the only side arm option (but you shouldn't need them anyway)


If you fancy the old school weapons.
Back pack: slap charges or grenades.
+Very short and handy in CQC
-No mid-range capability

Honestly, Mk18 is better unless you really like MP5.


For stealth tactics.
Bolt cutter and spy cam are very useful.
+Stay undetected (and gain high crit buff)
+Reasonably good CQC even in combat
-No mid-range capability


Back pack: slap charges or grenades.
Suppressor is optional.

+Very high crit
+Aims fast for CQC, but also surprisingly good at mid-range shooting due to high crit
+ADVAP ammo penetrates Level IV within 35m
-20 rounds per mag (not a big problem, since you deal with each hostile with less ammo)


Back pack: only frags or bangs.
Suppressor is optional.
+Very high crit
+1-6x LPVO boosts crit for mid range even more
+ADVAP ammo penetrates Level IV within 35m
-20 rounds per mag (not a big problem, since you deal with each hostile with less ammo)


No back pack nor suppressor.
Since you're using this loadout for SSI guys, Level IV is a must.
+Very high crit
+1-6x LPVO boosts crit for mid range even more
+Always penetrates Level IV armor
-20 rounds per mag (not a big problem, since you deal with each hostile with less ammo)
-Limited utility


If you absolutely must...
+Rocket
-Minimum protection (to be fair Raid Vest isn't that bad)

LMGs are heavy. We don't have many options.
Use behind covers to get huge mounted buff.

Short and lightweight. Better for moving and being offensive.
+Still good utility and protection
+200 rounds for some real suppression
+OK-ish for room clearing (not AR level but better than other LMG)
-Less firepower
-OK-ish for longer range shooting


High firepower in minimal form. Better for being stationary and defensive.
+Great firepower and crit chance even for long range
+Penetrates Level IV disregard the distance
-Less utility
-Extra squishy


Before you finish any campaign yet...
Just like LAMG, but even more limited
+OK-ish protection (less than that for LAMG)
+200 rounds for some real suppression
-Less firepower
-OK-ish for longer range shooting

Seriously, M249 is good enough. You should spend first few BHs for assaults.

DMR is surely for long range. They are also quite heavy.
And they are not that different, so we don't have many builds.

Pick either one:

• LPVO 1-6x + frags or bangs
  
• LR 3.5-10x no back pack

Suppressor is recommemded.
The idea is to let marksman participate room clearing
+Flexible, 3.5-10x scope for longer range, 1-6x LVPO for close range
+Full auto for room clearing
+ADVAP penetrates Level IV at all ranges
+Good (enough) long range crit chance
-Kind of squishy


Back pack: 3 slaps or grenades.
Suppressor is optional.
Let the distance protects you, not the armor.
+3-18x scope, good crit chance
+Basic utility
+ADVAP penetrates Level IV at all ranges
-Extra squishy, so keep enemies away and only at your front

AR + GL has good firepower, but definitely heavier and not as agile.

Back pack: only frags or bangs.
Suppressor is not recommended for room clearing.
+Relatively short and agile
-Quite squishy


Back pack: only frags or bangs.
Suppressor is optional and recommended.
+Good for mid range
+Surprisingly lightweight
-Lacks the scope to make accurate long shots, but you got 40mm HE grenades
-Quite squishy


Back pack: only frags or bangs.
Suppressor is optional.
+Good crit chance
+ADVAP penetrates Level IV within 35m
-Quite squishy, but with that crit chance? you won't give enemies much chance to shoot
-20 rounds

Need more CQC guy?
Supports and marksmen don't get enough chance to level up?
No worry you got M1014!
+Very strong within 7m
+Like other assault weapons, soldiers won't move it to back when using tools (much faster switching in and out)
-A bit long for room clearing
-No mid range capability (of course, it's a shotgun)