Living feels pretty un important when there is no consequence of "going down" and you can get resurrected an unlimited amount of times. So a small but significant loss of exp might add a lot more Value to the concept of survival in these hostile planets. It will also strengthen strategy and team work so that your squad mates and yourself dont die and lose exp. This exp loss can increase depending on your level or be a variable; the level of the monster that killed you equivalent to your level.
Maybe a glimmer loss would be more fair. Exp loss can be detrimental and new people to the fps genre would have a hard time leveling up. There is a consequence to dying while in a mission though. If all players die you have to restart the whole thing.