Sorry but thats not true, space marine is not more powerfull that anything else. About Concentration, duno its too powerfull but you still are not too powerfull if you see the overall, so i think its right.
concetration + -def aura + aoe + crit + avatar
2million dmg crits... its unbalanced as hell
There is one horrible issue with this map, purchasing.
It's already pretty difficult to find what you need, but you really start shopping at later levels, when creeps are omwtffbbq stronger. So if you run back, your mates die and the tenzillion units walk right into the circle. If I purchase the damn donkey, then I die because I can't control my hero while shopping.
Solution? Make the hero able to buy anywhere from the map. Also a little push the circle back, towards the shops. And make creeps a little itty-bitty slower and weaker.
EDIT: Oh and what the hell is up with those chance stealer shitfuckers? It's already difficult to spot them and run after/kill them. Then there is this retarded megafuckingslow aura which makes it impossible kill when they left your range. And since the lanes are wide, that happens pretty often.
Actually you can get up to 6.x million crits (at least thats as far as i can get) but thats not the point. You can still die, and there are still tons of builds who are as good as that or even way better. Balancing doent mean "uuhh 2million crits, thats too imba" it means compearing it to what is possible with other builds and there are tons of builds who can keep up with that, so its ok