Thanks guys for indepth info and board recommendations. Plenty to look up and read about!
It seems the general concensus is get a big wave board- makes sence

Anything around 100 litres is fine for me, and ideally a bit wider than my 60 cm FSW.
Swoosh- As for mast foot pressure, I think the biggest problem I face in conditions I described is simply crawling out on the FSW. Once on the waves it's not too bad- though certainly not as smooth gliding or bouyant as the big NSX. The FSW, for me anyway, certainly performs better the faster you go.
I'm very keen to ride a multi fin board, always hear good things about them. As I tend to sail like I'm surfing (driving off my back leg) I assume this would be rewarded with drive off the fins? I'm still talking slog and ride conditions where the sail is doing very little when on the wave.
Now to keep checking the for sale section.
Cheers Jase for the test ride offer. Mate, if you weren't 700 kays south I'd be on it in a flash.
Thanks again everyone.