Correct. Historical progression based on DOH is utterly meaningless to future progression. The only relevant factors for future progression are known retirements and planned growth... and the latter is of course aspirational at best. You could also consider corporate finances but I'd argue that's only a practical factor for pilots if they're really bad.

The big three are the best bets right now simply because they have a lot of near-term retirements remaining. That's about the only thing you can hang your hat on.