I'm at 1200TT and weighing two options-

1)Go to the regionals and wait for reserve time and upgrade time to start getting turbine time, then once im at ~1500 turbine PIC time, start applying to the majors

OR

2)Get a job somewhere that I can build 100hrs/month of turbine PIC time, hit 1500 turbine PIC time there, and then go to the regionals afterwards to get some 121 experience. After a year or so there, apply to the majors. The goal of this would be to get my pic time faster and still have 121 experience.

My question is- does United/Delta/American/Southwest consider 121 time more valuable than turbine PIC time? If the turbine time was in a caravan would that look bad compared to just getting my time more slowly at the regionals?

Time at a regional is better than non-121 single engine turbine PIC.

How old are you? Married? Kids?
Do you want wise (1) or fun (2)?

Go to the regionals if you can. It will only take you an extra 12-18 months to hit your PIC time goals, especially at the Amerian Airlines Wholly Owned regionals (Envoy, Piedmont and PSA) they’re upgrading folks as soon as they have minimums to be PIC... actually Envoy and PSA are so desperate for captains that they’re forcing upgrades regardless of if a pilot wants it or not.

They like both TPIC and 121. Ideally 121 TPIC.

Van TPIC alone will NOT get you hired by any Big-6. ASEL TPIC is only competitive for those if it's in a fighter. You'll need some glass jet time.

That said, if you got some TPIC in a Van and then went to a regional, you could apply to the bigs with both the 121 and TPIC tickets punched. I've seen 121 FO's who had previous turbo-prop PIC get hired without having to upgrade. Pretty consistently.