I like the idea of doing the Soldiers point run twice, if the logistics of moving cars/boards could work out without too much delay between the races?
You could either accumulate times for the 2 runs so no-knows who wins until the presos or handicap the second start by the finishing times from the first run?
Was thinking another option could be to start at Tanilba bay, paddle 2.2km due north (yes it's a hard slog but not for too long and saves a lot of driving distance to start at Swan Bay) then a right hand turn around the island and downwind to the finish, total approx 16.8km.
Travel times/distances based on google maps:
Nelson Bay to Everitt Park Soldiers Point (12km) = 18mins x 2 runs = 36mins (plus trying to do a car shuffle in between)
Nelson Bay to Tanilba Bay (39km) = 47mins
Nelson Bay to Swan Bay (65km) = 1hr 6mins