The aesthetic is on point.
It has a lot of potentials IMO.
Health going down over time is kind of a
"interesting to the dev but painful to player" mechanic,
and isn't mentioned anywhere in the game or the page.
In my biased opinion, I'd say add the option to toggle it off entirely.
If it's something you consider to be in the center of the game experience, it needs more balance and more transparency about how it works and why it's in there in the first place.
I think it is already on a pretty good path and has a lot of potentials.
Just keep in mind that new players are less proficient at the game than you, and think about how to onboard them into this challenging experience.
Best of luck to you on that project!