High and dirty has the right idea, although bribie is dead at the mo, tuna season for there is around April, southern Moreton bay and Moreton bay itself has "resident" long taill tuna schools but even these have been scarce and flighty when they do show up at theo.
Mackerel tuna are always about (false albacore over in the state's?) and readily eat flies if u can get your boat close enough, Harvey bay should fish well at the moment for a bunch of different species, tuna, queenfish, gt's and golden trevally on the flats on fraser island (yellow and white clousers).
A single hand 10wt would do u justice with a reel holding approx 250m of 30-50lb braid, clear intermediate lines in a tropic core, don't be to fussed on presentation, it's more about line speed to the fish that counts, that being said don't hack and slash your way through it
You might be able to catch Gavin at tie n fly outfitters on the sunny coast, he is out of the shop a lot working a boat further north.
The whitsundays should give u many an option to fish if u can get away from your sailing boat (not the most maneuverable vessel I'm sure) in a punt or tender (if it's safe to use to fish from that is).
For tuna surf candies tied with polar fibre in sea foam green with uv purple flash on top has been my lean on fly for over a decade and keeps working.
Clousers in white and white and yellow and deceivers to fish deep under mac tuna schools for bigger cruisers, clousers for flats fishing in h'bay to.