I've long thought of Ringo as the Dave Tough of rock'n'roll.
And as far as his skills going downhill, well, it must have started after 1970, because just listen to his work on Lennon's first solo album, Plastic Ono Band. Sounds kind of like a career highpoint to me.
And yeah, the BBC stuff is great. I was lucky enough to get a couple tapes of most of it in the very early 1980's, quite a few years before anyone thought of bringing it out on CD. Some local radio station broadcast the sessions (I don't know how they got away with it) and a friend taped it for me.