I think the best option will be a merger with members of A-10 and other select schools. You would have a 14-18 team conference (7-9 MVC schools, 7-9 others to match), with a good RPI, good locations, and the ability to send more teams to the dance than either conference by themselves.
I think you could see a couple of MVC schools decide to opt out and pursue other options, whether that be jumping up (Wichita State to MWC/BE), moving for football (ISUr/UNI), or to stay in a tightly knit geographic conference (Evansville?). For simplicity's sake, I'll assume a 16 team conference with two divisions. Here is a hypothetical example of what it could look like:
West: Wichita State, Indiana State, UNI, Illinois State, Drake, Bradley, SIU, MSU (assuming Evansville goes to Horizon league to avoid travel, but this is just an example)
East: VCU, La Salle, UMass, Richmond, St. Joseph's, George Mason, St. Bonaventure, Duquesne
Conference RPI: .5367 (average rank of 111)
MVC RPI (minus Creighton): .5312
A-10 RPI (minus defections): .5271
If we subtracted the worst A-10 schools and replaced them with schools like Belmont, Valparaiso, Bucknell, Detroit, and Denver, we could have an RPI of .5530 (replacing Duquesne, St. Bonaventure, and George Mason with Belmont, Valpariso, and Bucknell).
For some more comparison, here are some other conferences:
1. B1G: .5818
3. Mountain West: .5732
5. Big 12: .5546
6. Pac 12: .5522
9. SEC: .5380
10. WCC: .5316
11. CUSA: .5183
12. Horizon: .4964
We could be the 5th or 6th best conference with the merger. Without it, we run the risk of being outside the top ten (remember, we have a new conference for next year).