I'd *probably* go AA with that mix. I'm not as up on who has the best shuttle services these days...if US is overwhelmingly easier/more convenient, then Star Alliance seems like it'd be okay.

AA has the Challenges you could look into, although it might be tough unless you have some of the Seattle stuff up front and are buying midscale coach fares or higher. (See the AA FAQ for a detailed explanation of the new Challenges, Q-points, etc.)

Marriott might hook you with a fast-track to Gold. Unlikely that either will throw you free Plat without a status match. I like both MR and SPG...if you like Westins, grab your SPG Amex, maybe hotel-hop a little bit to hit SPG Gold quickly, and you'll do just fine.

If you're a full-time consultant at any sort of medium-to-large firm, call your firm's travel agency and ask about status comps and matches. They will frequently have better hookups than you could get cold-calling programs on your own. That's how I received a couple of my hotel mid-tiers to begin with. Even got a no-questions-asked Delta Silver one year... (I believe our firm's travel was coordinated by Carlson-Wagonlit at the time, but I'm sure Amex Travel and the other biggies are similar.)