I think this would have been fine with just aesthetic changes to each 'sequel', but there should have been a tighter focus on the intended effect. I think it either should have gone for 'upgrades' that were nothing more than a reskin (so a radically changed player sprite/background), or just gone fully surreal in an Eversion way. As an example, at one point there sort of seemed to be a tornado approaching in the background, but that didn't go anywhere. As it was, the joke fell just short of landing for me, but I think it was a worthy effort.
Thank you very much for the feedback. I kind of rushed the backgrounds and sound design since the jam appeared to be ending. I'm glad you brought up Eversion, though, because that was part of the inspiration (perhaps to the point where I've somewhat ripped it off by now :/ ). At this point in time, I'm not sure how much I'll add to it. For now I'd like to improve the controls at the very least, but otherwise I'll have to see how long I'll feel like jumping from jam to jam, and also decide which ideas are worth pursuing. Good night.