Major things
1) Mercenary camp is not well placed, the building can be reached from behind by sneaking.
2) The wall should have vision blockers to avoid exploits, those gates may be bottlenecks that can be blocked with melee huntress, while archers and casters can attack to the other side of the wall safe. NE advantage. Also tower build that area seems to be a benefit.
Minor:
3) Orange aerial creeps level 12 can´t be creeped by undeads until Tier 2 (web skill). NE advantage for the archers (Orange review of low level aerial creeps). The loot is a power up level 2, that may give more exp to the hero.
no more things I think, I still rate it 5/5 those things are easy to fix.