I think your loop sounds like a good one. Go for it!
I have not ridden Shadow Of The Rockies. But a year a go my brother and I did a big loop pieced together from CDT (Big Dog tracks) , Forever West (in ADV forum) and the Colorado section of the TAT. Here is the trip report in the ADV forum.
Hopscotch and Jack Danials Too
You could make a shorter loop out of the route we did.