747-200 are doing military charter flying for the next 18 months and there are only two of them.
DC-9s are complex because many of them are placed as spares. Marketing tried to pull 30 out of the desert and then shortly thereafter announced the parking of 40 or so but thirty never made it out of the desert (lack of crews to fly them). Point being we are still upgrading pilots to Captain on the 9 even with this announcement.
As for the airplanes Delta are getting, that is great, I didn't know, the more the merrier, however each company has planes that are getting older. I.E Delta older 767s which is why more 330s are being sought.
My point being, along with attrition, NWA brings a lot to the table with a significant amount of widebody flying/exclusive rights in NRT. Since the merger of USAir and America West NWA now has the oldest seniority list in the industry, barring maybe aeroflot. I also believe DAL brings a lot to the table, as well, I am just advocating a mindset of fair and equitable over imposed super seniority. Since the talks have been kept very closed who knows how close or how far apart the two MECs are from reaching an agreement.