If you can afford it I would recommend the surgery and if you really want it, try to be a pilot.
That being said, if things don't work out and you end up as a CSO, don't fret as there are plenty of cool jobs and opportunities awaiting you. Also don't let the "second class citizen" negativity get you down. While this attitude exists in certain communities, it's not as bad as you may be lead to believe. Speaking on behalf of AFSOC it's very common to see CSOs (FCO/NAV/EWO) in leadership positions. Our last MAJCOM/CC (3 star) was an EWO, and current one is a Nav. It's just a non-issue when commanders look past the wings and examine an officer's leadership potential. Some communities haven't gotten there yet.
1. Yes, you can have a full career as a CSO.
2. You will travel, probably more than you will want to. Locations and living conditions vary drastically between airframes, so choose wisely.
3. These planes will be around for a while. To add onto what Jdmuehle said:
The MC community often pulled CSO experience from the C-130 world, which is quickly transitioning to all J models. They will need to find guys to fill those seats. There likely won't be a ton of them dropping, but they should become more regular.
4. Kind of, but not related to being a CSO. You will be marketable after a stint in the Air Force just through leadership and organizational experience. Anything from getting hired back on as a civilian working for the military to a non-military 9-5 through a headhunting agency you should have no problem finding decent employment. A good bachelors/masters and good squadron jobs only help improve the odds.
Best of luck!