Yes we found this theme quite difficult, in that all the innovative ideas we came up with just sounded miserable to play haha. In the end we opted for the fun over originality approach :P Even so, I like to think we tried to put our own spin on it!
A better progression curve was something we wanted to look at but we ended up running out of time. We especially wanted to make the earlier levels a bit more immediately acessable. Would have been good to change enemy spawn rates by floor or something!
I'm really glad you enjoyed some of the powerups. We wanted these to significantly change the way the game was played and to also augment/detract from different playstyles. So far the feedback on these has mostly been pretty good! It's awesome you liked the presentation too. We had alot of fun with those.
Thanks for taking the time to give such great feedback and I'm glad you enjoyed your time playing :)