I thought the randomization of the doors was a good idea, but it gets pretty repetitive and I managed to go on a streak of losing all my hearts by opening doors. I think it would play a bit better if beating a level didn't come with negative consequences.
I also eventually ran into a bug where I clicked a door and got the bonus but wasn't transported to a new room.
Boss combat was okay, would have been nice to have them do more than stand still and fire the same projectiles.
Overall pretty fun though!