The positive: I love this concept. The art is super cool. The music is chill. The sound effects are on point. I liked that there was a well organized and functional menu that allowed me to change characters. The puzzles in the levels were super cool. Levels 1 and 2 did a pretty decent job of teaching the concept without being too much to take in for a new player.
The negative: I couldn't tell if the game was glitching or if I was just struggling with understanding the game mechanics but I couldn't get past level 3. It kept saving ghosts of me that didn't move at all (which is not something I was doing). I would try to save the ghost that I needed to advance but my actions just weren't consistently saving. This either needs to be better explained or a bug fix is needed.
Over all: With just a little bit more polish, I could see this being a game that puzzle gamers absolutely adore. Right now, I'm not so sure that it's playable past level 3 but I loved everything about it so much that I'm not even that mad about it. Hope this gets further developed.