I think the A-10 is a great conference, but I think the the MVC is just as good, and better on some dimensions, when it comes to basketball. Since the major conferance realignment in 2004, what total body of work are you referencing besides Conference RPI, NCAA bids, NCAA results, and head-to-head results? All of those measures would indicate that the two conferences are practically at the same level of quality for basketball for the last 5 seasons. Again, I'm referring to true conference strength and not equating a conference position due to the level of a single program like Memphis in CUSA and Gonzaga in the Big West.
I would put the A-10, MWC, and MVC is the first tier of conferences outside of the BCS leagues. The MWC, which is a pretty well run league, just signed a head-to-head agreement with the MVC for the next few years. With all the effort, the MWC is putting into achieving BCS-level stature, there is no way they would agree to such an arrangement if they did not view playing the MVC as something that would strengthen their non-conference schedules.
Based on the typical school profile, I understand why SLU would not want to throw themselves into an academic relationship with the like of Ill St, Southern Ill and Northern Iowa, but that is based on academics and not quality of hoops. Perhaps the A10 could (or would be interested) in trying to pull in Butler, DePaul, and Bradley to create a six-team western division with X, Dayton, and SLU. The league could then slice off some of the east coast bottom dwellers, like Fordham.