I have been wasting considerable time looking at this. The 4 teams(followed by the SP Rank) left in the PAC 4 will be Oregon State 24, Cal 51, Wazzu 62, and Stanford 71 with an average of 52. The ACC's average is 43.64. The AAC average is 84.92, followed by SB 91.78, MWC 99.25 and a weak C-USA at 116.
Let's just say that an average of under 60 and as close to 50 as possible is what the PAC 10 would need to keep playing with the big boys. They really only benefit from taking from the MWC is BSU 56, and Fresno 70. If they go fishing in the AAC, they can get SMU 49, Tulane 55, Memphis58, and UTSA 61. That would give them 10 The PAC10, and their average would be 55.7. A tad weak, but still within reasonable reach of the ACC anyways. But that is stop gap to save the conference. They can't really add more or it weakens the strength of the conference.
If that were to happen, I want to focus on what happens to the MWC, and AAC. With those teams gone from the MWC it s new average would be 106.4 and the new average for the AAC would be 96.6.
At that point, though, the MWC and the AAC would need to replace teams. Who's left out there to poach. The new rankings would be SB 91.78
AAC 96.6
MWC 106.6
MAC 109.16
CUSA 116
There really isn't enoughop teeams in those conferences to make a better one really.