Yeah, sure. Its definitely interesting.
Its always* fun when fantasy meets sci-fi.

EDIT: So, would the group be split at the start, or do we all begin from either the return party or subterraneans?
And yeah, the slight prejudice with the return party being seen as cowards and soft while the 'natives' as perceived as "hokey and primitive" is a nice take. I already have an idea for someone from the space-farers.