I think the idea itself is pretty nice. but the way you get there still must be discussed =/ when the player lands on that planet and if the thing the player used to get there is gone it gives the player the feeling of being helpless, defenseless and stuck on that planet which is awesome. it would be kinda lame if you could just leave. if the player is too weak for the monsters the player could try to avoid them and gather the materials for a device to send a help message to his ship
The caves would also be dangerous, but probably not so much. Anyways the planet is high level, (Thus warning) and if you die, you go back to the ship with no rewards, and wont be unable to go back there, since planet will have been consumed (You can find other planets with this quest though).
