If UAL and CAL merged, I hope many of the UAL guys get the clickers back out. It'd help empower the younger/junior CO pilots too, which would be good for unity across the seniority list. Nothing liked getting reminded of your past by your FO's for the rest of your career to drive you to leave early.
The UAL pilot group would be a great addition to CAL's (if the 2 sides could ever agree on an integration, that is). UAL's route structure would be good too - they got many of Pan Am's desirable route authorities, and of course UAL's history goes back to Boeing. With CO's 'most international destinations' it could work. UAL's management would be what'd I'd really worry about. The 'midas touch' isn't something they have much experience with.