I'd love to see more variety in the spaceships, and a sandbox mode would be freaking awesome!
I really like the game's concept, but I struggled a bit with the progression. Since the buffs from "good" ships and the debuffs from "bad" ships aren't that different, the optimal strategy ended up feeling like just spamming as many ships as possible. I think the balancing could be adjusted to make each choice feel more meaningful.
Other than that, this is a really good game!