I know, I know. Every once in awhile Tom's gotta come in here and ask for classical stuff.
I do have what I think are some decent requests, though.
The kind of stuff I would like BIAB to do includes certain symphonic things, of course -- Beethoven, Tchaikowsky, big string and brass sections working together, with woodwinds in support. Layered strings, based on the section setting, e.g., "a" could be legato mezzo-piano, "b" could be legato mezzo-forte, "c" could be legato tremelo, and "d" could be pizzicato.
My idea here is for the newer genres known as "epic" and "trailer" music. The former is often big orchestra sounds, particularly brass; choruses; and heavy percussion (huge impacts, tubular bells, etc). Think Carmina Burana. The latter is more diverse, tending toward faster strings, swelling brass, pounding pass, driving percussion.
I think combinations of RTs and loops could handle this stuff very well. I'm working on a few ideas of my own for it, but I'm curious as to what PG thought of the possibilities.