The ability to use the unit disable feature for only one team in a match would be a good addition in my opinion, i think it would be interesting as a way to make challenge style matches against the AI in the PVE sense. As well as potentially a lighter form of handicap for some teams, then the direct economic increases or decreases.
It would also be an interesting way to make a sort of light custom campaign if you wanted to, where you and a group of friends could make a series of matches where you slowly unlock units overtime. Of course it would also be nice to have an in game mission editor as opposed to needing to run an external program, as the mission editing and publishing software seems to be quite old at this point.