With a JFK base, sometimes you will do the few hour stop in ORD and sometimes you will fly direct to ANC. LAX-based guys do something similar using YVR or SFO as a stop. With a JFK base, there are enough hours in a pattern that you can only do two a month. LAX guys have the room to squeeze in another trip or a half trip (end-of-month overlap). LAX is cheaper for hotels and the office is within walking distance of the Sheraton. JFK can present some commuting difficulties because of more expensive hotels and the fact that (depending on where you live) you might have to fly into LGA and get yourself to JFK Cargo area. Lots of time to wear out your liver in ANC (sometimes up to 75 hours, but usually about 35 has been average for me.) I've only had one strickly domestic trip in the last year -- usually you go to HKG.
Pogie