MÖRK BORG is a meat-grinder OSR. There is a clear expectation that player characters are expendable, to the point that there's an automatic character generator for the game ready to go, since players are expected to be using it a lot:
SCVMBIRTHER.
D&D 5e is not a meat-grinder. That expectation for expendable PCs isn't there. Instead, the game pushes a zero-to-hero theme with PCs expected to (fairly) quickly level up in power, eventually reaching mythic levels. Usually through wanton violence.
Since Level Up is meant to be compatible with D&D 5e, I don't think it should go the meat-grinder route. I'm not saying that Level Up should go full story-game; as much as I like that scene and think that there are some very important and overdue lessons that D&D should learn from that genre, D&D 5e as it stands right now isn't that (it's closer to what some designers call "trad games", as opposed to OSR and storygames). If Level Up wants to remain compatible with D&D 5e, it should probably hew close to it in tone.
Except for, you know, the parts of 5e that really should be fixed, and which Level Up is in the perfect position to do so, but that's a topic for a whole 'nother set of threads, which will become more timely as Morrus expounds more on the design ethos and plans for the game.