We agreed with this one that the final level should be your actual game! Everyone thought this was the most engaging puzzle, and I can think of ways you could extend the mechanic, possibly even incorporating your switches and/or crates. "Baba is You with Slime" was suggested as a tagline!
The music spawns in a little loud, this is pretty common but maybe just ramp the default volume down a bit.
Overall really enjoyable with a lot of potential! Nice work.