If upgrade is essential to making it to a major and you really must have ORD, RAH will never get you there unless the upgrade time to hold ORD as captain changes significantly. When I left in May ORD was an 8-year base to hold captain and was shrinking on the captain side. Many majors are hiring regional FOs these days if you have the right qualifications, so you may be able to get away with it if you have the degree (with good grades), volunteer time, good recommendations, etc.

I loved my time at RAH. The QOL was outstanding. After about 1.5 years I always held 17 days off, all weekends off, fully commutable lines with 80 hours credit in ORD. The most legs I ever saw in a day were 4. At the time no Skywest guy could tell you that. Their senior guys were still slogging along getting 14 maybe 15 days off and working their butts raw with 5 to 6 leg days. That being said their contract has gotten better so someone from Skywest will have to chime in on whether this is still the case.