I beat The Ruin in Starbound last night and almost immediately started a new character.
Upon making it to the Outpost, I was startled to discover that the racial NPCs I had unlocked with each artifact were already at the Outpost! They were even selling me stuff and offering quests!
This leads me to wonder, what else is constant between multiple characters? If I go to the same planet on 2 characters, will all the buildings I've built with the first be there? Can I use this as a way to transfer gear between my characters?