the only change to this skill is one thing I think is just plane scalable but technically against the rules of D20.
Assist: you may assist Perform (any) with Perform (any). this way the whole band can play at once for one big Perform Check. the drummer, the horns, strings, dancers, all assisting the lead vocalist.
you can even assist your own Perform (any), with your own Perform (any other). it just takes separate actions for each and the “main” role must be rolled last.
(Did I just break Bards? well that’s ok cuz I still haven’t figured out exactly how to translate a skill check to a will save)
Dude, I’m gettin the band back together. >bu-dum-dum< >cheeeesh<