Played through the whole game and I wish there had been more. This is a fun concept.
If you want to work on this after the jam, I'd suggest either adding a time limit or maybe a limit on how much you can erase, because you could always cheese your way through the levels by painting very safe paths and then erasing everything behind you to gain pack the paint.
I appreciate that you had a look into Andy Warhol's art style for inspiration :)