Really satisfying to watch solutions that go perfectly.
UX could be improved a little, though, for example ability to place multiple of a type of block without having to go back to the hot bar, or a confirmation prompt on the "delete everything" button that it's too easy to click while placing blocks (or just design levels that don't require you to place stuff near there (such as making that part of the screen a bar that doesn't interact with the rest of the game world)
Really really wish I could save and watch back solutions, immediately going to the next level and losing your prior solution forever feels baaad, I want to show my friends what I did, even if it's just "play again / go next" as an option would let me record solutions