I can't imagine any band that could do Ian Anderson justice by focusing on J.Tull music exclusively. A couple or three tunes, maybe. But I just won't ever "feel" right watching anyone but him and his band do Thick as a Brick or Songs from the Wood.
A band that is able to represent the prog rock genre overall - a few Tull, a few Moody Blues, a couple of Yes tunes, an ELP or three, King Crimson, Utopia, maybe even toss in a little Rush for whimsy. And generously scattered with the Dead and CSNY just to make sure everyone is still paying attention
You'd need drop-dead gorgeous harmony and killer keyboards (and a moog) to pull all of this off. It'd have to be just a once every few months show, there's no way they'd want to set up a moog every week on one of those town square stages.
Now if you'll excuse me, I need to watch this:
Emerson, Lake & Palmer - Fanfare For The Common Man - YouTube