As of now there are no "plans to integrate" the companies. You know how those plans go. Talking to a few in the know, and the death spiral that MEH is in (financially) something will have to give. I do not foresee DAL/NWA giving up a MKE market. It is a perfect arena for them to use their 737-700 in. MEH looked at them as well. They may still get them, and that would be the DAL answer to parking the 80's, but as of now there will little or no West Coast lift.
Coming from the area, I can tell you that the MKE market is fiercely loyal to MEH. They are part of the reason the AAI bid failed.
NWA has always had a good presence in MKE. They grow and shrink. They finally bought a minority stake in MEH and stopped the fighting. NWA has a vested interest in MEH, as does TPG. I recall that TPG also has a vested interest in NWA. With all this money flying in close formation, I guarantee that the interests of TPG will be taken care of. They simply will not let the MKE market go to AAI. (If they do so it will be another of DAL's blunders.) I do not see that happening.
FWIW, they people that I know at MEH are hoping for the same. It appears that there is some positioning going on.
As with the DAL LOA, personally I think that DAL management was willing to give that to DALPA. The reason is this game plan is still a few years away. It is also good PR for DALPA to be willing to work with management (once again outside of section 6), get a few pay percentage points to their pilots bottom line and at that time come to a solution to the side letter dealing with MEH. As I have said before this part of the game is far from over.