Well, there are a few things:
1. Less security hassle when operating our own flights
2. A much wider variety of choices of types of flying and schedules than any other carrier, in quanities that most pilots can do what they like.
3. More extensive international route system than any other single carrier on the planet, bar none.
4. Extremely high caliber pilot group with varied and very impressive backgrounds, from the f/o I flew with recently who has a Masters in physics and a PhD in computer science to the retired former chair of the Joint Special Forces (retired as BG, all active duty), etc.
5. Very well maintained equipment. Unlike a pax carrier, if our airplane doesn't move the payload turns into "free-load", so a lot more emphasis on having everything working right, relatively. Not saying the pax carriers aren't safe, they are, but this is getting more into the dispatch reliability side of the equation.
That's a few, I'm sure there are more.