I expected a few "it ain't broken, don't fix it" but for the moment, I persist.
Actually, I'm more concerned about PCs than villains. In my other campaigns, I disliked the wack-a-mole effect of PCs doing down to 0 hp and back up fresh as a rose (lower hp notwithstanding) after being restored 1 hp. I found it cheapens the drama, and although I'm actually quite ok with D&D's abstract hp mechanics, this is its weakest point IMO in a more realistic narrative.
In this game on the other hand, I want to embrace the wack-a-mole. It fits with the genre. Characters go down during a fight and then get back up. Why? Because the fight is over, the bad guys has gotten away or completed his nefarious deed or whatever. No cleric or magic required.
Still, I don't want to remove the threat of death completely, and don't mind including injuries because again, the genre allows it. I haven't found the right balance however. If injuries have no effect you might as well not have them. If they are too debilitating they are just no fun at all.
At the moment, I'm leaning toward a houserule whereas successful death saves bring you back up to 1 hp (with penalties?), but I'm also contemplating doing something with HD, or allowing everyone a short rest at the end of an encounter, regardless whether you were reduce to 0 hp or not. There are many ideas on the table ATM.