My wife and I did this trip in the spring. A couple of things ....
The Confederate Air Force museum is at the Midland/Odessa airport and worth a visit. Don't miss the nose art gallery.
The part about lodging rates is dead on, $250 a night at the Holiday Inn in Midland/Odessa area. Call ahead and you'll find that rates vary widely.
We stayed at the Harvard Hotel in Fort Davis, very nice place. We had a bad experience at the Drug Store (restaurant) next door, but it was mainly service (or lack of) related.
http://www.harvardhotelandlodge.com/
I would really recommend that you go on down Hwy 67 to Presidio and drive the river road (Hwy 170) to Terlingua and on into Big Bend NP. In Big Bend the thing you don't want to miss is the Basin, where the lodge facilities are.
Alpine is a cool town, went there on an earlier trip. There is a Mexican "Fusion" restaurant on the west end of town that was fantastic.