Combat interface needs to improve.
I want to see multiple attacks and commands for various units.
I also want status problems to be introduced into gameplay (ex. poison, paralysis, wounded, etc)
Don't get me wrong, Glest is an Excellent game, but there are too many things that get on my nerves and things that can be improved.
As mentioned by daniel.santos, I hate when I have a stationed guard who automatically advances when an enemy is in range. There should be come kind of "guard" command that lets that unit attack an enemy in range, but return to its orginial position at the end of combat.