I just finished the last puzzle, having downloaded the game yesterday, and I really enjoyed this game. The difficulty curve of the puzzles felt pretty nice, the art was gorgeous, and the audio ambiance felt simple and relaxing. I liked how the last puzzle was the mountain with the diamond top, same as the shape you make on the start screen, it felt like a nice little way to come full circle. Also, this was probably not intentional, but the single note playing whenever you pick up a puzzle piece or snap one in place reminded me of the thatgamecompany game Sky: Children of the Light, specifically how flying past certain objects in a very evocative late-game area makes similar one-note sounds. That mental connection added another, more personal layer to the audio design for me.
All that said, I do have a few small critiques: The edges of more complex pieces were sometimes hard to see against the flat backgrounds, and in some of the later puzzles (the panda, the person, and the orcas, especially) some of the pieces were so small that they were a pain to work with. There was also a technical issue that I stumbled across with the panda, where I ended up snapping a lot of large pieces together off to the left, and when I finally did snap them over to the static piece, only some of the pieces gained colour. A lot of other, unsnapped pieces were accidentally hidden beneath the part that was snapped but uncoloured. I ended up needing to restart the entire puzzle to fix it.
None of these issues ruined my enjoyment of the game, though, I'm very happy to say. I downloaded the game on a whim from the racial justice bundle, looking for a simple, pretty game to relax to, and I got exactly what I was looking for. Thank you for making such a nice puzzle game.