Would you pay out of pocket for ATP-CTP or do you all think regional hiring will pick up enough by next spring that I shouldn’t worry about it?
No, but be prepared to ride the regional hiring wave later this year.
You're going to need time at a regional anyway, so doing ATP/CTP, time building, and ATP practical aren't a good use of your money. As @Jim123 mentioned, there's a lot of flux at the moment. Majors starting up hiring (plus FedEx and UPS continuing) will continue to create vacancies at the Regionals. At some point (probably quickly) the pool of ex-RJ guys from Compass/XJT will dry up, and hiring will be back to 2019 levels. I don't have a crystal ball, but demand for pilots created the ATP-CTP funded by companies as well as the RTP bonuses.
Skillbridge is good stuff if you can find a good opportunity. Socialize that with your Reporting Senior early, as they hold 99% of the keys.