Thank you for your feedback and kind remarks! I would have loved to do more (separate the tutorial from the main game, make the corridor longer, ...) but I started this jam halfway through and didn't have enough time. I plan to keep working on it to see what I can achieve by polishing it, and yes, my first step will be to revisit the inking mechanic to make it smoother and much more enjoyable.
I am currently considering a few different options that I'll try out, but I am wondering if you had a specific idea in mind when you said "adding a bit more squash/stretch or extra movement", in case it's something I didn't think about yet.