I'd say this is a fantastic game. Very balanced and gives room for tactical micramanagement.
Few things You should change in the interface which suck donkey balls:
1)Making upgrading easier to do. I lost battles while trying to upgrade units. It's slow and cumbersome.
2) The controls are non responsive at times.
3)Maybe make a pause screen where you can upgrade/buy units so enemies can't overwhelm you.
Apart from that, the game is stunningly good.