1. IT does not matter what you fly for the military, as long as it is fixed wing, you will be in good shape when it comes time to apply for the airlines. Fly what you want to fly, so long as you can qualify.

2. Flight time: Fighters - maybe 200-300 per year, could be more
Heavies - 400-800 per year, could be more or less
Drones - yes, you could get a drone, and it is worthless when it comes to an airline job.

Figure 11 + years minimum for Air Force (Pilot Training + 10 years once you get your wings)

Talk to an officer recruiter about financial programs. They are always changing. After many years, you can get the $25K/year bonus, if it is still available. If you go "Balls to the walls", you will be way ahead of everyone else, who are just balls to the wall

Oh, I just read where you said Navy or Marines. Sorry about your luck.