I personally think that there is just too many coordination upgrades in the mid game (even though you dont need that many). I'm at world 42 and i have 24 coordination upgrades just staying in the upgrade menu. Instead of giving the coordination upgrade every last 'stage' of the world, after specific worlds later (ex. world 25) it would be great to have a cycle of coordination upgrades and the 'resource related' upgrades on the last 'stage'.
Personally i think the game should add units that can deal AOE damage, since the game right now is pretty much about swarming. With AOE damaging units added, the game would balance out. Having to use different strategys to beat the opponent.
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