Moonjen, I wouldn't mind if you added piccolo, digeridoo, koto and tuba. But I was just trying to explain what I thought Shambles probably meant. I'm all in favor of playing whatever you think sounds good -- ignore the "rules," and tradition be damned. But if you refer to a "bluegrass lineup," I think most people would think of the small group of instruments I mentioned (with the addition of dobro, which I neglected to mention).

Jeri, I think you got it just right.