Well this was a fun little game! Fun in the overall structure, the effortless gameplay (it helps having an extra computer where the game can be in focus), and neat array of available upgrades in features. Feels like as far as active gameplay is concerned though, this could use some changes, something to motivate the player. As has been mentioned, more noticable effects of upgraded equipment or other stats would've been nice. As far as the lack of imminent danger goes, I'm fine with that, as having a danger would mean also having to focus on the game and occasionally revive/retry/etc, something that wouldn't work well with the way this game otherwise work. I like how enemies evolve too, though all in all it really is very simplistic, would be nice with a more wholesome version of this, with more of everything; the elaborate suggestions that've been mentioned already. Nice work!
-cd-