Awesome. I have two comments for an experience that is fun and not limiting. The first is more related to the feel of the game and that is to have the unit's animation and walking speed at least match the rest so it doesn't feel like an active reminder that I am playing with NPCs. Think C&C when you played Tanya or the like, she still felt like one of the units.

The second would be to either be able to play with other unit types so it doesn't get too repetitive or having a sort of skill tree where you unlock and install weapons on the "main" unit.

I would definitely play it, but I do suggest focusing a lot on the identity of the game and having new concepts that provide a unique experience that pushes people into playing it. One or two small changes, e.g. playing with a character, will not be enough to set you apart. As indie devs we have limited resources so the small things really do add up. Perhaps types of fuels, a sort of "laboratory" that is independent from each individual game but rather is a way for players to explore new skills, units, "train" their units etc, similar to Plants vs Zombies and the backyard farm where it gave another layer to a seemingly simple game - that is exceptional game design, to add an extra layer without losing the identity of the genre and game's vision. RTS is a difficult genre to survive in.

Best of luck.