Thanks for the detailed review, and I wholeheartedly agree with all you've said! I also thought of Peglin but to me Peggle/pinball has so much more left to give than Peglin did, and this was just my first game jam attempt - and I thought I could make it functional in time because I knew how to make gravity and bouncy objects.
Interesting about the experimentation. I feel that users should be encouraged to experiment and ideally have surprising 'aha' moments, but figuring out the UI is never fun - I think that should just be intuitive. What do you think?