I love that name, it's adorable on a baby boy and it's a strong, manly name throughout life.
My cousin's neighbor adopted a baby, he's part native american, and they named him
Peter Gerald. They were also thinking of
Peter Jared. I think
Peter Gerald is best, as well as
Peter Frederick and
Peter Anthony. I don't think
Peter John or
Peter George, only because they're short and since
Peter is as well, I would use something with maybe 2-4 syllables.