Looking for advice to implement requested feature.

Hello, LD buddies.
By far, the two most asked additions for our game were more maps, more creature types.
As we are now returning to development and I'm completely refactoring the creatures AI system, it's a good time to ask which unit types you think would fit/you would like to see in the game.
We're interested in any suggestions, critics and other feedback you're willing to give.
Thanks a lot in advance!