Have you thought about a compromise between relo and weekly travel?

Here's what I did on my last gig where I knew in advance just how long it would be. I got a room at a Residence Inn for the duration. There's your Marriott Plat. I booked by calling the hotel and asking for the sales manager, and got a rate well below what a short stay rate would have been, plus, with the long term stay, there was no sales tax (this will vary by state). I stayed over most weekends, but flew home for about 3 nights every 3 weeks, to check my mail, water my plants, see my friends, etc. That's 15 or so R/T's for you, should get you pretty close to first tier status.

When I ran the numbers before proposing this to the client, 7 nights at the long-term rate was about the same as 4 nights+tax at the regular rate. The airfare savings more than covered the weekend's meal costs.

This all worked out as a win/win.

The client got to have me for the full work week most weeks at the same or less travel cost.

Keeping the hotel over the weekends made travel much easier when I did head home(no clothes to schlep). Choosing a RI meant I had a kitchen, so I had an option not to eat out when I didn't want to.