85-health monk?

I was wondering how effective an 85-health monk would be compared to a 55-health monk. I had this divine symbol as a reward from pre-searing that reduces health by 20.
Will this work?

Would have a slightly higher chance of dying, but not much. So yeah, it can work.

with that you can die once and become a 8HP monk for a while which is stronger than a 55 monk in most situations.

Very possible. Before the -50 health icon was "discovered" and became popular with it, the original invincie-monk farming build was the 105 monk. It still works fine.