ok for hornbows, but still hard on energy. i believe favorable and read the wind damage doesnt stack, not sure though.
and no res sig
yes they do stack. different sources always stack. RTW is preperation. FW is a spirit. you could also use winnowing instead of FW if you have a few warriors on your. if you have more than 1 ranger one bring FW and the other bring winnowing.
predatory season is my personal fav since it screws healing.
RTW and favorable don't stack, i tried this before. i don't remember all the data, but when i tried comparing the results of RTW, FW, and RTW+FW, i noticed that there was no difference in damage.
Quickshot is screwy because it has a cast time that doesn't seem to actually do anything; your attack speed actually does affect it (so hornbows will still be shooting slower.) Boost your Expertise, consider dropping Wilderness Survival (you're only using it for Unguent anyway), and consider dropping Favorable Winds.