It is interesting how many permutations some of these 'bands' have/had.
Bringing it back to the Beatles; I would have been OK with Klaus and Billy replacing Paul - I don't know if it was ever actually a possibility given John's desire to go it alone - but it was a nice 5-minute daydream; I was just listening to the Ringo album a few days ago and the first track reminded me of the gossip back then as it had that lineup.