Technically, AS is considered a legacy carrier (as is Hawaiian). As others have said, I really don't see DL revamping their entire program just for Seattle. Instead, we will likely see more targeted promos like the recent double-MQM and the 100K DL Amex sign-up deals. I think FT community is somewhat of an outlier when it comes to mileage redemptions. The percentage of flyers fixated on exotic business class trips on foreign carriers (you don't actually expect us to redeem miles on pedestrian DL do you?) with a stop-over and an open-jaw (and all at Saver levels, of course) is probably not as significant as you assume.