I'm in LAX (AA UA hubs), use to be in MSY (SW "hub") both as elites. My boyfriend was in DCA/BWI (SW "hub"). Worked out well for us, though at LAX harder to get upgrades on NW, almost impossible on CO.

Usually have to connect so yup more miles....

Having DL and CO as options helps as well, since it doesn't always work out to fly NW due to overpriced tickets or poor schedule