I'd argue that what Cropredy needs is more 80s acts - the kind of thing that will appeal to people currently in their forties/fifties, because let's face it, the original FC fans and Cropredy attendees are well embarked on their seventies now and are going to be less and less likely to turn up, for multiple reasons.
I'm not quite in my mid-fifties and the 80s are absolutely my era for mainstream pop music. Quite a few of the still-working acts that came out of the 80s are recognised for their songwriting and musicianship and would sit very happily on a Cropredy bill.
I realise that Nile Rodgers and Trevor Horn are strong nods in this direction (and they both have 70s crossover too) but the net could be cast wider.