I'm NYC-based but 80%+ of my travel is transcon (NYC -> SEA, SFO, LAX, SAN) or international via AS partners.
I keep the AAdvantage Executive Card as my non-AS strategy; it gives me access to Alaska Lounges and Admiral's Clubs, as well as Priority Boarding and free checked bags on AA, which means I can even buy basic economy and not suffer too much. My goal is for flying not-Alaska (only a few times a year) is basically to not be charged extra fees, so priority boarding and free checked bags is basically the Elite-lite that I need. For the 3 times a year or so I need to fly a different airline, the lack of upgrades doesn't really matter (and as a AA Gold, my chances would be nonexistent anyway). $450 / year seems like a good deal, and I even get to share the membership with a few other family members.