Yeah, reworking blood seems like a really good idea.
I am not sure how “fleshed out” the stomach idea that is currently being developed is, but I guess something similar could make sense.
A total “blood count” that gets somewhat reduced every time you get hit, and a lot reduced when you are bleeding/heavily bleeding. Low blood count results in dizziness and maybe even fainting. While a too low blood count will result in death through bloodloss.
Blood count is slowly increasing up to a cap while the player is not bleeding.
This also opens space for a “anaemic” and “much blood”(?) trait, respecitvely reducing max blood count or increasing it.
The more I think about it, the more awesome it sounds.