For an idea for a "planet" how about this? Sword and Tech. Think Sword and Sorcery but instead of magic there is technology left behind by an advanced ancient civilization, called Relics. Instead of sorcerers there are Scientist, studying ancient tomes called User Manuals, trying to unlock the secrets of the Relics. So it would be mostly not advanced (think Conan the Barbarian) but there would some advanced Relic technology that pops out of the scenery with it's distinct look. Pretty cool, huh? Out hero could be a hunter of Relics and his pal a mad Scientist :)