If it's all about eyeballs and national brand, why not go after Sanford and get at least some foothold in CA?
Seems like the top 4 would be Oregon, Washington, Sanford and Utah if that deal could get done. If Oregon and Wash hold out for Big10 invites, then maybe you have to sub in AZ and AZ State.
Colorado belongs in a regional conference with Co State, Boise St, Wash St, Oregon St, etc. They add nothing to a super conference.