This was pretty fun! I like that all the weapons felt pretty different, and upgrading them felt nice and felt like they made an impact. It was fun getting to use the new stuff, and having them level up based on how much you use them really helps to encourage the player to try all of them out. Controller support was quite nice, in general it felt better to play on, but I think I may have had some issues using the tether once I started using the controller. I was able to manage without using it since I only started past the first level, but some of the jumps felt like it wasn't catching correctly. The little familiar also didn't seem like it'd attach until after I jumped from the ledge, which made me really apprehensive to do so since I didn't want to fall to my death.
Also, I think there was a bug on the first level at least - hitting the water while gliding seemed to just take me underneath the water instead of killing me, so I would just fall into the void until I returned to level select.
Liked the designs for the characters, and the enemies really gave off an alien feel, so I think you succeeded there. Also, the train was very nicely made, too.