re: Migrating on Earth
Our minds may indeed inhabit other worlds, but they may not do it in human form. Or we can genetically modify humans to survive in just about any environment.
Either way may certainly keep our descendants from living restricted lives, at least on the worlds they are meant for.
As for visiting Earth, they might want to do so out of curiousity, but for every generation after the first colonists, their new world will be home. Earth will just be a far-off land their ancestors came from. Being a "minority" here won't be a concern for them.