Sir Paul would play complicated and sophisticated bass parts that other bassists would not attempt. Listening to McCartney, his playing makes me think that he isn't just a great bass player but instead is a great musician who happens to play bass guitar.
My teen-aged son has become quite a Beatles' fan. He made a great observation about While My Guitar Gently Weeps. Although Eric Clapton was brought in for the featured part, it was the rhythm parts of Paul and Ringo which combine to dominate the song. I've come to believe that this strong bottom-end to their songs is one of the reasons that their music was superior to their contemporaries and why it has such an enduring character.
You are correct. I have never heard anything approaching the sheer musicality and arrangements of the Beatles.
Yes comes close.