I can offer a bit of info.
IMO opinion Bill’s book that you mentioned is the best book on hiking in the Beartooth’s…I lived close by for a few years and used it. I found it to be both accurate and extremely helpful. I still make it back from time to time..though the last few years I have been heading to Yellowstone more.
Routes…You could choose several and be fine. I would consider his difficulty ratings a bit off. Just my opinion. He usually under estimates their difficulty, but not terribly. Many believe the Beartooth’s are the best off trail hiking area in the lower 48 so your options are unlimited. I am a trail hiker and don’t feel overly comfortably venturing off trail for long so I never really made attempts at this but always wished I hiked with someone more capable of these trips so I could learn.
Obviously its bear country. I found Griz to be more toward the Yellowstone side of things, but realizing they can be anywhere is always a safe notion. I have seen a few black bears on the trail, but they always ran. They are hunted in the wilderness and in my experience this makes them much more fearful of humans compared to other known areas. Finding a place to hang a bear bag was always possible whether it be a tree or a large boulder. I personally believe a bear keg is over kill.
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