They will think outside the box and outside the footprint. In fact, Fox may push them to do just that because there really are no good choices within the footprint, which is why they stopped at 10 the first time around. The choices are not likely to get any better by waiting. So, they make the move to the school with institutional fit with the highest profile:

Gonzaga

I'm obviously not the first one to think about them. There are all of the obvious objections. Too far. Too many time zones. Sitting out there on an island. It will never happen. We can't change the distance, but we can note that except for Portland, Gonzaga already travels between 900 - 1500 miles for all the rest of their conference games on the West Coast. So, the distance will increase, but they're already getting on a plane for every sport in which they compete in the WCC.

As far as time zones are concerned, that is a big problem. West Virginia is already finding the combination of distance and a time zone change to be a major problem for them. And that's only one time zone. But WVu is traveling west and coming back east. Going in the other direction actually helps on the return trip and is much more doable. For the rest of the league it's a max of one trip out west per year. Not a big deal; many of them already do that.

Being out on an island is something that can be accommodated. Find a second team out west that draws big attendance, has a high profile, will boost TV ratings, is always competitive, and has the private school institutional fit with no football. That would give Gonzaga a travel partner and allow the rest of the league to pick up 2 games with one road trip the way that the PAC XII does. Such a school does exist:

BYU

If the BYU is serious about going independent in football for the long haul, adding them for all other sports would be no different than adding Notre Dame, which the Big East would do in a New York minute.

No one else available would increase the conference's competitive profile and TV ratings the way that the combination of Gonzaga and BYU would. In fact, I would venture to say that such an announcement would be a blockbuster. Fox would love it. I suspect that they're already thinking of it because if I can see it, so can they.

In spite of all of the travel and logistical obstacles, it's really an offer that Gonzaga and BYU can't refuse. Right now Gonzaga has a ceiling on how far they can grow their program because they play in a mid major conference comparable to the MAAC. The home attendance for all the other WCC schools except BYU averages in the 2000-3000 range. Some are less. It's really awful even for the better schools in the league. Gonzaga has outgrown that conference.

It's even worse for BYU. What the LDS wants out of BYU sports is exposure. That's why they are adopting the Notre Dame model and going independent in football with their own TV deal. But the WCC gives them absolutely nothing for the rest of their sports. The Big East would be a dream come true for them with major market exposure and a big time TV contract.

I think there is no doubt that Gonzaga and BYU would make the jump and I also have no doubt that the rest of the league can manage the logistics. The PAC XII and the Ivy League have already shown how to manage schedules to create paired scheduling on weekends to minimize the impact of travel. It's very doable as one western road trip per year at worst. Frankly, for Gonzaga & BYU it's not much different than what Miami had to manage in the old Big East or what Colorado is managing in the PAC XII. Except that Miami had no travel partner.