1. Delta's "best of the best" attitude has been suppressed to the extent that 2/5th's of the list was "acquired, not hired." Much of the bigotry which resisted unity in 1999 to 2000 had to be put on the back burner to create the hegemony necessary to make Delta + NWA a success.
2. Yes, and it should be exclusive to ALPA members by design. If others want to play, then they need to Certify.
... and at the risk of starting a flame fest, there was a difference in the way Delta's selection process worked. The Delta process resulted in a very homogenous group of people who work well together and I would summarize that as professional, putting the mission before their personal desires, and above average smarts (which is true of pilots in general, IMO).
The logo from 80 years ago, in today's terms, would be; Safety, Efficiency, Comfort. Management has been striving to build bridges back to Delta's culture. I would hasten to add that C.E. Woolman did not outsource half of the airline's work. In this employee survey it was pointed out "Outsourcing was not a Delta value."
There have been many good friendships built across merger lines. Really, Delta is a new Company since 2008. This change is for the better. The Company's employees are executing very well. As such Delta is developing a new culture and we're in a bit of a golden age. I see no reason why that culture can not be extended to our brothers flying Delta passengers at the express carriers ... and management is going to have to figure out how to staff DCI, in as much as DCI is 40% of Delta's flying, it is a Delta problem that must be addressed.
As always, I believe the best answer for a union is unity.