suggestions:
-have an autosell feature where any item with less + or equal to the highest plus for that type of item is automatically sold. Inventory is too cubersome and detracts from actual gameplay.
-show numerical stats, and the numerical effects of the special ability proc
-The green levels are not good because you can get unlucky. Giving the player some amount of unit summoning and spellcasting might mitigate that.
I found that zerg rushing with mass hood the rabbits, then spamming the fist attack spell was a pretty effective way to quickly clear levels, before that I did mass kangaroo + attack spells :P.
I found that upgraded armor piercing turrets are really effective. Decent damage to non armored targets, insane damage to armored targets. Hackers, the only counter will reduce dps so watch out. Fully upgraded Emp towers shut down shields really effectively, until you run into hackers (even then, those towers will sometimes hit them once when they pass by). Fully upgraded stun mines are awesome. Preventing attacks allows you to teleport your mastermind over for a couple of free shots.