I have a TS so take that into account:
In many ways a TS is more convenient. If you can take it home you can do all your maintenance there. That will save you money. We store ours at home.
We regularly go day sailing and the set up takes about 20 mins (not including the people). Its not the hassle people think in my experience. Mast up storage is great but you have to pay for it and you also lose some of the convenience of portability and home maintenance. Obviously nothing beats a marina berth but $$$.
I would have thought the advantage of being able to lift the keel and even dry out at places like wathumba etc would be a big plus for you. Think RL28 and all the Ross 780s made for Qld customers.
If you are going to pay for storage, dont want portability (by the sound of it) and are happy to only visit waters with 2m depth you might as well get a keelboat as they are cheaper per foot.
There is a Magnum 8.5 for sale at Tin Can bay. Keep that in mast up storage and it would be an ideal family boat. Or keep it in a pen anyway!
I would like a keel boat for longer offshore work but down here mooring and berths are quite expensive so l stick with my Castle 650.
Btw the Castle sleeps 4 and is about as quick as a Noelex and faster than a Sonata 7. They are also really light. The keel retracts so you can dry out nicely. Really easy to set up. But small for 4 people...you can't have everything!
Hope that helps. In the end it depends on you usage patterns and budget to an extent.
Regards Stephen