Yeah I think you're right, there maybe needed a few more levels to build up to the last level; however totally understand that with time constraints its hard to do those things. Personally I felt the number of levels and length were great for a jam game.
I did in fact get stuck often on the last stage and its probably due to the volume of things that were happening, lots of NPCs the spikes etc. and narrow corridors made it harder to actually get around than I expected.
Cool idea using GPT to generate a rough level design that you refined to make use of btw :)