Nice mod, and nice additional characters. However, they lack a bit of build potentials and perks that synergize well with aspects of their kits.

- Surprised Pika seems kinda torn between its ultimate / energy regen builds and a stun build, but kind of lacks options in either. Pika can only stun with his ult, which is a bit limited, and means you HAVE to build your ultimate regardless if you want to stun the opponent. I think effects based on the shocks would help a lot in that regard. Maybe an epic perk along the lines of "After 30 shock hits, deal stun for 0.1 seconds" or something along those lines (numbers can be tweaked) would help in that regard, where you can stun without your ultimate if you so choose. A perk along the lines of "Each time enemy gets stunned, gain 10 Energy Regen for the battle" would also really work well, as each stun would basically be also +1 damage for each shock you have. A perk with "overclock : gain 1 temporary shock for the battle" would also be really cool I think, probably as a legendary perk. Pika just lacks a few perks to have more interesting builds. I think giving Pika access to music notes would be really cool as well. Also, have something mentioning ketchup, Pika's one true love.

- Spike Knight has access to milks, but no unique perks that have anything to do with healing and/or milks. I think something along the lines of "after dealing X damage with thorns, launch 1 milk" or like shark test, "every 9000 healed, get a shield bash" would be nice. Something like the 66 flex hits giving permanent strength but with the pins would be a cool mechanic as well, I think. A perk that would give you 1 permanent thorn for every 50 or 100 pin hits would be cool and more unique than just thorn quest. Something similar for shield bash would be nice, although since shield bash is more rare, I think something like "shield bash gives +1 temp armor for the battle" would be a cool epic or even legendary perk.

- Death Star kind of lacks synergy with its black hole relic. Yeah it protects it against the enemy's first ultimate generally, but it still feels a bit lackluster as its "main gimmick". I think some perks that trigger "after the first 6 seconds" (so at the same time black hole triggers" would play well into a build that needs to wait a bit to truly get going. Maybe something like "after 6 seconds, get +20 strength for the battle" or "after 6 seconds, get +10 armor" would be interesting perks to have. I also think Death Star ONLY having energy regen as a way to build its ultimate is a bit sad. Maybe a perk like "each time a TIE hits, Max Energy goes down by 5" or something along those lines would be nice.

Those are just some ideas, hopefully you'll take them into consideration to make your mod even better!