I shelled out for a Thermarest NeoAir full-length and I use that with my Hennessey Hammock. Down to about 40 degrees, I use an ALPS Mountaineering Razor Sleeping Bag Liner and a Sea to Summit Reactor Extreme Thermolite Liner. If I feel cold, I put on some wool. I have slept comfortably to 45 without the ALPS Razor, so I expect this to be just fine.

When it gets colder, I use an EMS Mummy Bag, the Solstice 20. I have slept down to 10 degrees in this bag. With the liners, I suspect I can approach 0.

The hammock stays significantly warmer if I tie the rain fly really low, leaving a small space so condensation doesn't form. Wind has not been an issue- Hennessey's asymmetrical design means rocking is minimal. I also try to pitch it with windbreaks. Either other trees, a hill, or a house- whatever. Same with a regular tent.