What I really want in any game is Mechs. This might be a stretch to do since the it either needs to function flawlessly or it needs to use some sort of pre-made animation (which would be difficult to fit on so many different designs) but if i could have one thing, it would be giant robots. more like a Gundam style as well as any other style people like such as mechwarrior, or the Big O, whatever Giant Robot floats your boat. of course it would all be up to the player. maybe they could have some sort of skeleton that you could build off of and that skeleton would have the pre-made animations and you would just be putting on the armor and weapons. might be a bit too much, but it will always be a small dream of mine.
For now I can just play pretend by building a ship in the shape of a Gundam even though the arms/legs don't move. if they added some sort of rotors like on Space Engineers or some sort of moving parts mechanic then that would be more than enough for me.