Howdy from up on the Pittwater. Things have been pretty quiet this year amongst the Sydney hangers after a good few group outings last year and before. Work, life, interstate moves, and weather seem to have put people out of contention over the last months. In my own case every time we try to plan an outing lately it gets derailed by something or other... Hopefully now spring is here something will get organised again here on HF, so if you're interested to check out various gear options you may get a chance.
My own suggestions and experience since getting my first hammock about a year and a half ago (YMMV):
1. You will need a bugnet most if not all year round in the greater Sydney area.
2. If you are a back or side sleeper you will be good to go in a gathered-end hammock, but if you prefer to sleep on your stomach you may find a bridge is more comfortable (though they generally weigh more).
3. If you go with a UQ from the outset, there's no need to get a double-layer hammock. UQs are way more comfortable than pads IMHO. For me, a 2/3 UQ plus a footpad is fine down to about 5°C, so I'm looking at getting a full-length UQ before next winter. For many folks they find going below freezing is fine without needing a full-length UQ.
4. A TQ is not only lighter than carrying a sleeping bag, it's much easier to get in and out of in in a hammock and I find it more comfortable as well since it doesn't restrict you from rolling over.
5. I found having a small pillow in the hammock made it way more comfortable. The pillow needs to be connected to the end of the hammock or ridgeline so it doesn't keep slipping down.
6. Tarps do more than shelter you from the wind and rain, they also stop possums jumping off the trees into your hammock.
7. I reckon casuarinas make the best hanging trees round here: strong, smallish diameter, no widowmakers, no sticky sap, generally near to water, and little undergrowth under them.
8. Be warned you may never want to sleep on the ground again.