Out of PIT, I believe most of the CVG and all of the JFK flights are on Delta Connection, so the first leg at least would be RJ. Most JFK flying in the northeast is also connection.

As for upgrades, depends on when you fly. I'm a Silver that is batting 100% this year and 75% last year, but I'm a leisure traveller that can set my own schedules most of the time.

As for awards, I can get them pretty easily. Sure, I thought about going to TPA this weekend last minute, but I would be stupid to think I could find a SkySaver. It's all about being reasonable - plan early, you can get them. Only times I've had to use SkyChoice is when I'm travelling to popular destinations at peak times, and then only when booking only a month in advance.