I was playing a multiplayer game with another player (just us). We had just started a new server with new characters and at some point I started to recklessly kill zombies with a screwdriver (headshots) thinking I'm Conan the zombie slayer from the previous save. It got me killed, twice.
Seeing as the game was fairly fresh, I just spawned in a new character and basically I wasn't penalized much at all for the recklessness.
Here is my suggestion: You can enable "Only the good die young" mode where you can spawn a new character, but the cost of positive traits are increased by 1 point each time, thus making your build weaker each time you respawn. This, in addition to losing all your progress could make the price of death feel a bit more impactful.
If that system doesn't work, maybe you can lose a random positive trait, gain a random negative trait etc. I'm sure you catch my drift.