I don't think you're asking the right question. Any move to break the MWC involves probably 4 teams. If you're taking that many teams when maybe San Diego State's the only team from that league that adds any value......you're diluting your own value to a large extent.
Does that make sense? To me.........no.
Part of my thinking is that much of the P5 is there due to traditional affiliation and not based on maximizing media value with respect to current US population.
When considering that, the Pac taking a strategy of bringing up some G5 and owning the west has some merit.
Since I don't feel like working, I decided to play with state population and the number of P5 programs per capita within those states.
While there are certainly other factors which matter besides in-state population such as national brand, I think that playing in a P5 conference and winning/getting ranked quickly changes that. So I'm thinking in terms of where you might make bets that the elevated G5 has the resources to turn into a significant asset.
1. CA. 39.2M pop. 4 P5. 9.8M per P5.
2. TX. 29.5M pop. 6 P5. 4.9M per P5.
3. FL. 21.8M pop. 4 P5. 5.5M per P5.
4. NY. 19.8M pop. 1 P5. 19.8M per P5.
5. PA. 13.0M pop. 2 P5. 6.5M per P5.
6. IL. 12.7M pop. 2 P5. 6.5M per P5.
7. OH. 11.8M pop. 2 P5. 5.9M per P5.
8. GA. 10.8M pop. 2 P5. 5.4M per P5.
9. NC. 10.6M pop. 4 P5. 2.7M per P5.
10. MI. 10.1M pop. 2 P5. 5.1M per P5.
11. NJ. 9.3M pop. 1 P5. 9.3M per P5.
12. VA. 8.6M pop. 2 P5. 4.3M per P5.
13. WA. 7.7M pop. 2 P5. 3.9M per P5.
14. AZ. 7.3M pop. 2 P5. 3.7M per P5.
15. MA. 7.0M pop. 1 P5. 7.0M per P5.
16. TN. 7.0M pop. 2 P5. 3.5M per P5.
17. IN. 6.8M pop. 3 P5. 2.3M per P5.
18. MO. 6.2M pop. 1 P5. 6.2M per P5.
19. MD. 6.2M pop (6.9M w DC). 6.2-6.9M per P5.
20. WI. 5.9M pop. 1 P5. 5.9M per P5.
21. CO. 5.8M pop. 1 P5. 5.8 M per P5.
22. MN. 5.7M pop. 1 P5. 5.7M per P5.
23. SC. 5.2M pop. 2 P5. 2.6M per P5.
24. AL. 5.0M pop. 2 P5. 2.5M per P5.
25. LA. 4.6M pop. 1 P5. 4.6M per P5.
26. KY. 4.5M pop. 2 P5. 2.3M per P5.
27. OR. 4.2M pop. 2 P5. 2.1M per P5.
28. OK. 4.0M pop. 2 P5. 2.0M per P5.
29. CT. 3.6M pop. 0 P5. N/A per P5.
30. UT. 3.3M pop. 2 P5. 1.7M per P5.
31. IA. 3.2M pop. 2 P5. 1.6M per P5.
32. NV. 3.1M pop. 0 P5. N/A per P5.
33. AR. 3.0M pop. 1 P5. 3.0M per P5.
34. MS. 2.9M pop. 2 P5. 1.5M per P5.
35. KS. 2.9M pop. 2 P5. 1.5M per P5.
36. NM. 2.1M pop. 0 P5. N/A per P5.
37. NE. 2.0M pop. 1 P5. 2.0M per P5.
38. ID. 1.9M pop. 0 P5. N/A per P5.
39. WV. 1.8M pop. 1 P5. 1.8M per P5.
40. HI. 1.4M pop. 0 P5. N/A per P5.
41. NH. 1.4M pop. 0 P5. N/A per P5.
42. ME. 1.4M pop. 0 P5. N/A per P5.
43. RI. 1.1M pop. 0 P5. N/A per P5.
44. MT. 1.1M pop. 0 P5. N/A per P5.
45. DE. 1.0M pop. 0 P5. N/A per P5.
46. SD. 0.9M pop. 0 P5. N/A per P5.
47. ND. 0.8M pop. 0 P5. N/A per P5.
48. AK. 0.7M pop. 0 P5. N/A per P5.
49. VT. 0.6M pop. 0 P5. N/A per P5.
50. WY. 0.6M pop. 0 P5. N/A per P5.
Taking the above, here's what the Pac expansion possibilities would bring in state population.
SDSU: 7.8M by itself; 6.5M with FSU.
FSU: 7.8M by itself; 6.5M with SDSU.
SMU: 4.2M by itself; 3.7M with UTSA.
UTSA: 4.2M by itself; 3.7M with SMU.
UNLV: 3.1M
CSU: 2.9M, but it splits a Pac market.
UNM: 2.1M
BSU: 1.9M
The above are raw numbers. Then you'd have to look at home metro and what share of the market care about college sports + what share of the P5 pie they would get + national appeal (which dramatically inflates a Notre Dame, for example).
Based on this, I think a Pac-12 which added SDSU and FSU would be the way to go. For a Pac-14, SMU and UNLV are the next 2. I don't see going past that.