Buckethead did an entire album on his 6 string banjo after he had back surgery a few years ago. The cover of the album even has a human spine on it, IIRC. I'll see if I can find a link to the album and cover art.
Bucket seems to be able to play any guitar-like instrument just as well as he plays guitar. TBH, he's an even better bass player than most of the big names, like Flea, too. Maybe not Victor Wooten but Bucket is damned good.
I agree, my brother learned banjo. We took lessons back to back from the same music teacher. When I realized he could make more full sounding music with those rolls, I decided I had to learn 3 fingerstyle myself.
Banjo is a beautiful instrument, you can do anything with it.