Thank you!
Would you believe, the ball mechanic actually started as a button-hold thing, but I ended up getting confused at what to hold and went for the up/down transition instead. The ball toggle button came in later. It felt a little overwhelming at the time, but maybe it'll be something that's easy to get used to? It should be easy enough to re-implement as an option, at least.
And yeah, the first level is a bit clunky as an intro stage. Mostly, it's 'cause I ran out of time at the level design stage, and wasn't really sure what kind of level would best fit the ball mechanic.
Thanks for the feedback, though! It'll be very helpful if I try to work on this some more afterwards!