Thank you for taking the time to write such detailed and insightful feedback! I had decided not to participate in this jam due to lack of time that I could dedicate to it and my lack of experience, but I found the theme very evocative and spent some time coming up with ideas for it purely as a design exercise. One of the ideas I had was this tile puzzle and it was so simple I thought I could keep the scope to a level that I could complete in time. It required no animation and almost no art and only takes a single click from the player as input on each level.
My main goal with my first jam was really just to deliver a complete experience that fit the theme. I've mostly only done little prototypes and haven't done the end-to-end building of a full game and publishing it. I thought this would mainly be a learning experience for me and I was frankly surprised to hear that people enjoyed it given how simple it is. I think part of that is just the inherent satisfaction that one gets from watching the chain reaction with its little pops :)
I don't really intend to build on this further, at least any time soon, but if I hadn't kept the scope so limited, I would have added in tiles that the player would need to rotate and/or empty spaces that the player would need to select tiles to fill, in order to make a viable solution. I think that would have added the missing complexity you're talking about.
Thanks again for the feedback and encouragement! This jam and comments like yours have given me new confidence and I'll definitely keep making games :)