AFAIK, the window is closed, I think largely because it's very difficult to buy sim time at the moment. They're getting their own sims which should free things up a lot. It's been a while, though, I would guess it would open back up soonish.
DFW and SEA are common. ATL I think, maybe less so recently. Plus every and anywhere else. The Secret Squirrel stuff seems to fly exclusively between the same few airports, but you know, if I told you I'd have to be killed by the Internet Opsec Police.
The Vegas flying is its own little minibase, you are not home based. On the plus side all you do is fly back and forth to Hawaii, with a day or two between flights.