In regards to new players, I think it a simple change in the dialogue of the "beam of light" might clear up what happened to them and how to get back in the game.
It's also not obvious straight of the bat that you can even ress, you just end up in a spaced out zone that looks like a storage for dead chars, until you come across the light.
This might put people off or make them thinking they're stuck in some kind of locked up boxed zone for ghosts, logging before they'd even bother to find the beam of light.
But marking corpses? I don't know. Perhaps a small notice in bottom of the description saying "This corpse still seems to have some life in it, although it's slowly fading."
It seems a bit far-fetched and crude in most cases to have such a message, ressurections or raises are often enough bordering the breaking of immersion as it is.