I really like this type of aesthetics. It feels very clean and polished. I feel like the level design was very good (except for that level 3 activator that was quite confusing). It would have been very interesting if the levels had allowed us to continue interacting with the previous level to solve the puzzles. Because apart from this pretty cool transition between levels, the nested structure of the levels has no impact on the gameplay.
But overall it was a great game. I really like it. I think this kind of mechanics have a lot of potential :)