and Washington staying. If you try to stay as the PAC and just add 2-4 teams to replace USC and UCLA, you have to be dang sure Oregon and Washington are staying. Not viable without them, and I don't think you can count on them long term (or maybe even medium or short term).
And that says nothing about the difficulty of figuring out who those 2-4 teams you try to add are. Just not many good potential adds left.
So ya - either dissolve and every team for himself, or merge with the Big12.