A potentially fun little thing you can try when a player character dies. It’s inspired by S01E02 of The Twilight Zone.
When a character dies, have Death show up and talk to them. Give your player the option to argue with Death about any unfinished business their character might still have in the world. If Death deems it important enough, they’ll let the character live until that business is sorted out. But since Death’s schedule is immutable, they’ll instead have to take someone the character cares about.
The details here can be handled however you like. For example, if your system of choice has death saves, you can treat this as if the character had succeeded at them.
Portray Death as you see fit for your game, as their concrete form isn’t important for this mechanic to work.
Also, you can either have the PC choose a person that Death takes in their place, or have Death choose for them. Whichever sounds juicier to you.
Since this incentivises the character to keep putting off their unfinished business for as long as possible, you can have Death return to them periodically for check-ins at inconvenient times.
Dungeon Merlin