lots of potential here, I can see how deep these mechanics can go and congrats on making such an interesting puzzle game, I always appreciate those a lot
I think difficulty is the main thing holding it back right now, some of these mechanics could be explored in 10 individual easier levels before getting to the "interesting" levels, that sort of thing is absolutely necessary to ease players in especially if puzzle games aren't so much their thing
I think it gets harder too quickly, if you will (and for a game jam, hard levels aren't so well received in general, just something to keep in mind)
also make sure your UI scales with the window!! on high res monitors you can barely see anything
overall tho this is sick, flipping an hourglass is a goldmine for puzzle concepts I've noticed lol