Yeah I understand. Time constraints are part of jams after all, you must work with these limitations.
I understand wanting to have an intended solution. To elaborate on my process, I did try to design them with an intended solution in mind, but often when I tested them I found several other (and sometimes better) solutions. But in this case I decided it was totally fine to leave multiple solutions because it made everything less difficult and didn't remove the fun of trying to figure out which hands must hold each other. So I guess that's also why it was faster to design than levels with a single, intended solution.
But I already found your game nice, even if it's mostly a proof of concept, you're right I feel like there's a lot that could be build upon here.