I love good feedback, thanks a ton!
About the damage over time, good point. we didn't have time to implement more visuals for it, therefore it's very unclear for first timers and seem like a bug, we planned to have flickering heart or last heart becomes poisonous.
Your last nitpick is our nitpick as well, we discoved it quite early that you need to just wait quite often, but we didn't prioritise that.
Thank you very much for feedback!