I saw him on video a couple of years back. I think he also chews gum WHILE he's singing somehow. Funny, I thought he looked bored. As if he was thinking, "I really should be doing something with my feet......"
A lot of Beatles tunes start out with the chorus. If ever I get in a rut with forms, I usually listen to one of their albums. Also, as far as solos go when just playing with you and your instrument, you don't have to be a genius, you can just play a chordal variation of part of the melody. The Beatles did that a lot, too. But, they are/were geniuses.