Hi Hawaii,
There are several great things about SUP....
Fitness aspect - I find it far more enjoyable than a run or a bike ride... do you want or need good abs !!?? Get on a SUP daily !!

Time on water - yes it will skyrocket, you can SUP around Melbourne & the coasts on pretty much anyday of the year. Even when windy, you can find a sheltered spot.
Even in Melbourne's winter, you won't be in the water too much, so the cold water is not a big issue (in my opinion). For flat water paddles, thermal gear, or "skins" are more the go, once you know you're not going to fall in !!

Yes, you can surf a 12 Glide, or a 14 Glide.
Hook up with the King of SUP Melbourne, DJ, and he can take you for a spin on the glides. I'm sure DJ will be on here soon. DJ's always on the look out for the next downwind day!
Simon
(in Torquay)