Interesting mechanics and nice controls. I think the particle effects add a lot to the game aesthetic and overall it looks quite nice. I definitely think that adding some SFX, even basic ones, will add a lot to the game. I thought the progression curve was solid. The second to last puzzle was the trickiest I think, and getting to that trickier puzzle at that time / pace felt quite natural. Expanding the lobby / main area might be something you could capitalize on... I could see how more variance / detail could expand your game world / add some intrigue to the world.