2 frames saved in the first level by starting 2 frames earlier.
3 frames saved in "I am a prisoner to Pactolus" by collapsing all roof blocks, eliminating the need to wait for a jump later.
3 frames saved in "My burden only grows" by prioritizing the leftmost roof block.
1 frame saved in "My world collapses" by starting 1 frame earlier.
11 frames saved by working around the issue where holding arrow keys 1 frame earlier doesn't work (not 15, since 4 levels don't benefit from this).
2 frames mysteriously disappeared while doing above. There wasn't any visible side effect, but I somehow ended 2 levels faster and I don't remember which. Figuring out what happened may lead to more time saves, hence why this is a WIP yet.