This is a really good puzzle game that combines Sokoban mechanics with bonding rules inspired by chemistry!

The rules are simple, with a few new mechanics added as you progress.

The complexity feels exactly right to me, and very satisfying: You can mostly solve the puzzles with pure logic, combined with a bit of trial and error to get a feeling for the puzzle.
Often, puzzles seem relatively simple at first, but require some out-of the-box thinking. In many cases I had analyzed all options that seemed reasonable to me, but found myself scratching my head as I still couldn't solve the puzzle. Then slept on it, and later discovered options that I hadn't considered before, which allowed me to solve the puzzle.

The puzzle selection screen displays each puzzle in a miniature view, so you don't have to randomly click on puzzles if you don't remember the name of the puzzle you're looking for. Progress is non-linear, so if you can't solve a specific puzzle atm., you can try some of the other unlocked puzzles.

All in all, I can hardly think of anything that I don't like about this game, and IMHO it's really well designed. From what I read, the bonding mechanics in this game aren't a 100% accurate adaptation of real life chemistry, though. As a layperson, I can't comment much on this. But at least the game seems self-aware if you create a molecule that is not supposed to exist. And the game works really well because of its simple rules; changing that might make it harder to analyze the puzzles, and plan ahead.