Alright, finished the main story and I'm a bit confused with what I'm supposed to do at Cruel Chamber in the Coping world. Up to that point I'm still missing: Musical chairs (world VII), Wiggle room, Cascade (world IX), Playrooms, Lockmess monster, Trash Heap and Bonefish (world X). Lockmess monster in particular is the first one I feel like I've already exhausted my options and got stuck with off by 2 solutions.
Waka really gives the impression that there's a better solution but after experimenting a bit it seems very few choices actually matter in the final move count.
Also got a couple more optimizations along the way.
Spoiler for Frigid Engine solution:
Spoiler for Jar of Nothing solution:
Spoiler for Six Bits solution:
Spoiler for Tetric solution:
I'm actually curious what the listed move count solution looks like for most of those because I'm finding those optimized ones as my first solution.