alright, thanks!I cannot think of a hammock with a built in rain fly. I have seen hanging tents before online but they were very expensive and I would not concider them a hammock.
You will most likely end up having to get a set for your different requirements. My personal favoriate hammock is the ENO. I just use a small trap from walmart just big enough to cover the hammock part for a rain fly. I am in the SE so I don't have much use for it, but for warmth you can get one of the under-quilts. You can also use your sleeping pad in the bottom of your hammock like I do and see if that keeps you warm enough.