I’ll be DMing some more 5e soon and I want to take the opportunity to try some different ways of playing (I’ll post my own suggestions as comments so they can start their own discussion threads). What alternate rules have you tried that you thought worked well? They can be larger changes to the game or little QoL tweaks (though if you can respond to the suggestion with “at this point just play [different game] instead” then that’s probably more than what I’m looking for!)
This one’s short and sweet. At level 4 PCs get the Score Improvement AND to pick a Feat. This has propagated throughout my whole group, but the original DM that started it reasoned "I think a lot of Feats are really cool, but a lot of people aren’t comfortable passing on their first Score Improvement to pick up something situational. So they get a freebie, because I want to see what uses they come up with.
I’ve seen a variant of this where everyone gets a free feat at level 1
As PC’s progress, falling to 0HP in combat gets less and less meaningful. So I have used a rule that whenever a PC is at 0HP at the end of their turn, OR fail a death save, they take a level of exhaustion. It makes the 0HP yo-yo more dangerous, and makes it so “death” has some longer term consequences.
My group uses this, but with a separate temporary exhaustion (we call it Trauma) that goes away on a short rest. Still handily serves the purpose of discouraging yoyoing without being too punitive.