This game was way better then I thought it would be.
I haven't played all the games yet. But I actually think mechanically this game is one of the best interpretations of the Corruption concept so far. It actually feels very much integrated to the gameplay rather then being a visual or storytelling element.
I actually liked how you don't explicitely explain what the effects of corruption are, as figuring them out and having an Aha moment that I really enjoy from puzzle games. It was surprisingly solid in terms of design. I read some other people talk about getting stuck or cheesing puzzles, but I didn't encounter anything like that in my playthrough.
Of course, the main thing for feedback would be the presentation aspect of the game. But I think you know about that already. I think for future jams, finding a team that can focus on art or presentation can help a lot. You seem to have the design aspect of the game down, and getting others to help you can free you up a bit more to focus more on level design.
I could see there being more complicated puzzles later on that showcase the corruption effects more.