I would caution trying to overhaul previous projects, I've seen so many other games uncompleted because the dev wanted to do too much, leaving the original to gather dust.
For now, if you were gonna return to the game I'd just worry about the sprites. At least then, if you got burnt out the original would be a good state.
Oh it's not anything I plan on doing anytime soon. This project entirely was a spur-of-the-moment thing, given that it was for a game jam anyway. If I do come back to this to overhaul it from the ground up, it'd be with the full intent on completing it.
And if I'm being honest, there is a certain sanctity in allowing a game jam submission to remain as itself. It is why I'm especially hesitant on doing too much with this current version of the game, and why I'm honestly not too upset by the concept of leaving this as is for a good while.