One question I'd ask Pete if I could is how his relationship with Neil Aspinall changed after Pete was dismissed from the Beatles. Neil was the father of his half-brother, but it's a story that's rarely told. I don't know if you'd feel comfortable asking him such a personal question, though.
Perhaps you can also ask him how he felt once his drumming was finally released into the official Beatles catalog, when ANTHOLOGY 1 came out in 1995.
I've got nothing to say, but it's okay!