The PAC 10 will be the last conference not gutted to look for expansion, but they will not be making picks solely to catch up with the rest of the country. If they did not feel that the teams they would be looking at did not bring more money to the table, then they would decide to stay at ten teams.
For the purpose of this discussion however, they do make it to 16, and every team has a purpose for being there. The first team the PAC 10 will look to add will be Colorado. Colorado has wanted out of the Big 12 and hopes that they will be able to recruit better out west.
Colorado is a good academic university and has tradition in their program, and even though it has recently fallen on hard times, a good season or two could bring in a large market for the PAC 10.
The second team the PAC 10 would want to take would be Utah. The Utes also have good academics and bring a large market in Salt Lake City, and a football team that has recently proven itself worthy of facing elite competition, defeating then SEC runner-up Alabama in the Sugar Bowl in the 2008 postseason.
The PAC 10 would then target Kansas, because it would bring an elite basketball program to the PAC 10 that could compete with UCLA as best basketball team in the Country and in the Conference.
Even though it would be expensive traveling the the Westernmost states, Kansas would accept because the financial benefits would be better than staying in the crumbling Big 12. Then the PAC 10 would invite Air Force Academy. This would be purely a financial move on the part of the PAC 10, as the AFA brings little to the table in competition, as football recruits rarely want to join the military, but many people go to the games for the service academies, whether it is to support their country, are in the Air Force, or have served in the Air Force.
To go along with that, the Air Force also has strict Academic qualifications. The PAC 10 would also want to bring in UNLV to bring Las Vegas into the PAC 10 and has a good basketball history. They would also want to bring in Fresno State to capture the central California market, and someone who will bring in a gritty football team willing to play anyone, anywhere, anytime.