Well sadly, Dupre, I missed WOW this year, but I do recall at the show 2 years ago there were a couple of Top dressing aircraft performing a rather nifty display routine. Maybe something of novelty might catch the organiser's eye?
Here in UK, we did have a Tiger Moth display team called "Diamond Nine" but sadly they disbanded a couple of years ago. However I know of one Moth pilot who set up his own outfit called "Captain Neville's Flying Circus" & he does one man shows in a deH 82 at Shuttleworth, Moth Fly ins etc.
Re Warbirds, not that I'm an authority on this, but some pilots are ex RAF, the Hannas for eg & some of the boys who display at Old Warden, but then someone of the late Tom Middleton's calibre made it from flying Saabs commercially, to running Biplane Adventures at Wanaka & becoming Sir Tim Wallis' chief pilot, test flying the Polikarpovs etc. I guess he proved anything is possible.
Hope this is of use? Out of interest, how was Wanaka this year?