Before testing some builds i got very good results with characters using Kondor CQB rifle, Snakebite rifle and .50cal Sniper rifle, all of them have medic skill and can save himself without help. Literally the chars are the best doing his work but sucks in others things (except for the heavy sniper, put him in the vehicle with the weapon or as passenger and using other heavy weapon and will do the highest dmg!)

Things to know

LW = Ligth Weapon
HW = Heavy Weapon

For now this is my assault character, good doing quick and "big" dmg, good survivality and a bit tanky!. Play him intelligent, use corners and be close to walls to detect near enemies, i don't add grenades or shotgun because is easy to find looting :) kill humans in 2-3 burst with kondor, the clue is the attack speed, i love it.

This sniper have the same build as heavy but shoot more faster, the counter part is the range, 22m vs 30m, the good part is the versality, can use any light weapon and be dangerous but control his hp or will die quick.

This char is very good healing and doing dmg very quick at long distances, it's like a turret and good to clear the way for the assault char, kill humans mostly in 1 shot, robots are more harder but vs them i suggest to aim to his arms, disarming or break his arms, on robots is better nulify them than kill faster.

The dog has the best max skill, medic at 190% literally makes flash heals, his running speed works very good to explore and atract enemies to an ambush, using him with grenades, to set traps or we can change the point's invested on traps and put in mechanic, running speed or melee attacks to make him more usefull (i don't like it melee but it's a option). Usually i give him the heal packs of the team because can heal better for the high skill (190%!), play intelligent guys!

I'll be adding more build, i'm testing a melee build, a minigun build and a trapper/lockpick, so later on (maybe 1 or 2 weeks) the guide will be updated :)