Well, the Compass flow is ending in the near future and is not available for new-hires. Endeavor has a streamlined interview process but it is unclear if that will be available to new-hires either. The SSP hires go to Delta in seniority order, so if they extend/modify the program in the future that could be a consideration. Beyond that I'd suggest looking for a regional with a domicile where you want to live or that is easy to commute to. Domiciles for each regional are listed here on Airline Pilot Central. Just about everyone is hiring like crazy and offering signing bonuses and other incentives.

Aside from Compass and Endeavor, Delta has historically hired a good number of pilots from ExpressJet (ASA). However, that airline is stagnant while others are seeing ridiculous seniority movement and short upgrade times. The fast movement places are currently Compass, PSA, Trans States, Mesa, and the like. These things tend to change however, so again I'd focus on domiciles/commutability and pay/benefits. I'd steer clear of Republic as everyone I know there is pretty miserable. YMMV.