I really liked the game, I tend to play it when it gets a new update of some sort, I have finally managed to beat the hardest mode, here's what i think about most of the varmints:
medic: feels very..... win more, its doesn't feel very strong early or mid game, since it doesn't have that much health and healing such a minor amount isn't gonna matter much if it dies really easily. I suspect it will be better with the final release of the game when there are stronger enemies and varmints.
magician: looks strong on paper, but is just too frail and doesn't scale well late game, it's evolution, wizard shows some potential, but haven't really tested it.
soldier: extremely good early game, decent late game, but tends to fall off late game, resilient is a very strong ability, allowing it to survive multiple fatal wounds over the rounds, feel like its evolution, mercenary is also suited for late game with its ability to use points as extra damage, overall a pretty well balanced card that has its uses.
gym rat: very good varmint to have, can be a bit awkward to use but having 1 feels necessary due to how strong marathoner is, permanent stat buffs are very strong in this game, overall it's a strong varmint but is balanced by it's removal of stats and the necessity to evolve it quickly.
farmer: the varmint seems really handy, synergizing extremely well with gym rat/marathoner due to it's ability to cycle cards quickly in hand plus it's evolution: chef, gives a varmint +1 +1 which is extremely useful along with having a slightly better version of the farmers cycling ability.
Saguard: really feel like this class was the strongest, my winning lineup for the final battle was 4 metal cactuses along with 1 saguard, I really feel like the pure stat buffs are just so strong throughout the game, saguard basically has "get 4 health deal 4 random damage" and metal cactus improves on that with dealing 1 damage at base stats which goes a long way when upgraded with chef and marathoner.
Overall, I felt like saguard was the best varmint, with gym rat and farmer being necessary to have for there stat buffs, soldier is decent with it's survivability, damage, and mercenary evolution. magician felt the weakest, while healer felt like it was a bit weak now but might be more viable when the game comes out and there's more waves of enemies.
nice game pardner