Right now the future of the Pac-12 is very murky.
While it's true that Mora has recruited well on paper, UCLA has been one of the Pac-10/Pac-12's best recruiting teams for years and years and it never translated. Last year UCLA posted a good record, but they folded like a chair when facing challenging competition. Plus, Jim Mora was a mostly terrible coach in the NFL, and I'm not going to forget that because UCLA over-achieved for one season. We'll see where they are at in a couple years but right now they lack the physicality of Stanford and the pure speed of Oregon. I think they are pretty much on par with teams like USC and Texas that haven't turned elite recruiting classes into elite football teams in recent times. That might change, but I'm still waiting to see a truly dominating team before I crown them.
Oregon was one of the best teams in the country last year, and they have most of their core group returning. If Oregon has more than 2 losses this year, I'm putting that squarely on the new coaching staff. Oregon's group of players are good enough to make the national championship game. But a new coaching staff means big time uncertainty. Chip Kelly may not have been the best college coach (Saban), but I'd argue that he was clearly the brightest one. That's hard to replace, and if there are philosophical differences with the new regime that could hold the ducks back as they were tailor fitted to Kelly's blueprint.
I'm still not sure about Shaw, but I under-estimated him last year. Harbaugh left a heck of a legacy behind, but Shaw managed it better in year two than year one. It was a small sample size, but I'm a fan of Kevin Hogan, so far I think he looks like a cross between Andrew Luck and Kirk Cousins. Their O-line and front seven are amazing. They play like bullies. Extremely physical. I don't think Stanford is better than Oregon, but Stanford is clearly the "toughest" team in the conference and maybe the most physical team in college football. They exposed Mariota as I thought they would in pretty much the same manner that Seattle exposed Kaepernick. Kaepernick still went on to nearly win a SB, though. Just the same, if Mariota can get by Stanford I think Oregon could potentially get to the national championship game.
I'm officially ambivalent on Sark. It's not that he's a bad coach but he strikes me as more suited to the NFL than the college game. He's a clever X's and O's guy, hires outstanding assistant coaches and is very smart, but he lacks recruiting panache and struggles with roster construction and you see the same glaring roster problems year after year (O-line in particular). He'd fit in well in the NFL especially if paired with a good GM. But in college, I think he's middle of the pack.
Rich-Rod really impressed me last season. It will be very hard to replace what Matt Scott gave them, but his system is known to get results from unheralded QBs. If we knew more about Arizona's QB situation I'd be tempted to pick them for the Pac-12 South.