Oh, this was fun! Thank you for providing the cheat sheet to help me find the final few. Good hiding places! Funny dialogs. TBH, I am glad the battles were easy as the main fun is in finding the aliens and reading their descriptions and dialogs.
Bugs: I could not trigger the Washing Machine Alien, tried all sorts of things. In one of the closests, I fell through the floor and ended up inside some no-space and had to restart the game (Windows).