And yes, if OR and UW want to join (probably not) then take them. I do think that CO has a lot to offer — even though they have completely crapped the bed since the scandal two decades ago. They 'have history' in the B12. That said, I see them trying to stick with OR and UW (+ Cal and Stanford).
As a BYU fan, I would NOT take uu. The B12 would benefit from taking uu (10 years as a 'p5' school has upped their perceived importance).