Just keep in mind that picking up the Northern Tier that way will ultimately send you over four mountain passes in a row in WA.
Another option is to simply stay on the Trans Am to the coast. I fond some of eastern and central OR somewhat borning (and hot and dry even in early September)
Thanks for the response Indy. I think my sister will be joining me for the last 1/3 of the ride, and the four passes on the NT route might result in me being pushed in front of a logging truck. I think I subconsciously overlooked the Trans Am because I assumed it would be worse, and I also assumed that central Oregon would be dry and boring. It probalby makes more sense to take the TransAm, especially since I hope to go back and do the NT from at least the coast to Glacier one day.
If anyone else wants to chime in I'd love to hear it. I seem to recall Jamawani/John Egan may have mentioned that he had an alternate route through the Sawtooth mountains, but I don't recall reading it anywhere. Looking at the West, I think I'm reconciled to the notion that it is not the mid-west or South, and I may have to carry at least a minimal amount of cooking gear and food at times.