Hi, Welcome aboard!
I don't have a lot of answers to your questions, but on the final snapshot for the current bid that closes tomorrow there are still 19 unfilled 737 FO spots in ORD. There are 0 on the 320. In fact, the ORD 737 FO staffing was increased by 19 on this bid, and they were allowing 22 320 FO's to leave the category without replacing them.
One other thing you might think about is ORD 756 FO. That category is growing as well. It might take a little longer to get into that, but is still going relatively junior.
Good luck. Wear your half-wing with pride. It's good for a lot of free beer!