A recent interesting example of a way to fix this is CrossCode, an RPG/maybe Action RPG. The way they do it is you heal to full quickly out of combat, but if you remain in combat and get longer and longer kill streaks, it increases your odds of getting rare drops (and might improve exp/money gains as well, I haven't tested that portion). You have to weigh the risks of continuing to push on at red health vs going for more high end drops.