The AF Reserves offers a bonus only in critically short career fields such as OR, ICU, ER, and Flight Nursing. The bonus is $15,000/yr for a 3 yr contract. You would only qualify for the Post 9/11 GI Bill if you were on active duty a certain amount of days after 9/11 happened. I am currently active duty AF and will transition to the reserves in December since I will be starting a civilian nurse anesthesia program and will be using my Post 9/11 GI Bill to cover the cost. Even though the school I am going to is a private school and the GI Bill only covers a portion, the school I am attending participates in the Yellow Ribbon program and will cover the rest of my tuition. So basically, I will have free tuition, a housing allowance of $1800/month and a stipend of $1000/yr for books. I can't complain at all. On active duty I also get the $20,000/yr bonus for the 4 yr contract I signed with them 4 years ago and I was able to save well over 6 figures to live off of while in CRNA school since I moonlighted a lot on the side.
You are right that deployments in the reserves are optional. On my unit, we have several AF Reserve nurses who work as GS nurses at our military hospital and they do their drill on the weekends. They said if you get tasked for deployments, there are always others who will volunteer to go for you. If push came to shove and they really needed you to go as an ICU nurse, you could decline the deployment and switch over to the Individual Ready Reserve (IRR) where you will not deploy because you will be placed in an inactive status. I have also verified this information with several Reserve Chief Nurses, since this is the only reason why I am leaving active duty is to finish CRNA school and definitely don't want to deploy during that time.
As I am typing this message to you, I am currently deployed to a Forward Operating Base (FOB) in Afghanistan. Been here since September and will be out of here in March home in my own bed. It's been a good deployment and the awesome thing about deployments is you get work outside your normal scope of practice. Since we only have 2 anesthesia providers, when we have mass casualties, I've been trained to intubate patients, place central lines, and arterial lines. I do my anesthesia machine checks in the morning and go through all the required checks. It's awesome. I run the Level I and the Belmont Rapid Infuser in addition to my duties as the senior ICU and trauma nurse. Nowhere in the US would you ever be allowed to do it as an ICU nurse but when you are deployed, its about saving our troops lives.
Good luck to you. The Air Force rocks!!