a few thoughts:
1) Murray State makes all the sense basketball-wise, but is not in a major metro. In this case, adding Belmont with them as a travel partner makes some sense. Maintains a public/private balance, and it's a two-hour bus ride between them. BUT
2) I wonder if there might be push-back from university presidents about adding Belmont or Oral Roberts due to their religious orthodoxy? We already saw a some chatter arise with Oral Roberts during the tournament, and though I don't think Belmont is as severe in their orthodoxy, plenty has been made about it in the past. I'm not trying to start a big fight on here, but it has to be thought about. With the private institutions - Drake and Bradley are secular, Loyola is Jesuit, Evansville is UMC, and Valpo is mainline Lutheran. Those are *not* going to be peer institutions, even the Christian ones, in terms of campus orthodoxy.
Of course, the Valley does have Dallas Baptist as an affiliate member right now, which is run by the Texas Baptists. Baylor is the flagship university of that system. They seem to be between Oral Roberts and Evansville on this kind of thing.
3) Speaking of - is there any mention of Dallas Baptist wanting to go D1 anywhere? That would also secure a private, major metro school that the conference already has a relationship with. I looked around and didn't see anything. But they would fit the bill of what's been discussed.
4) Even though I'm a fan of a private school here, I think Murray and Arlington make the most sense (assuming they're on the table). With Texas booming, I think it'd be dumb not to plant a little flag there. I gotta think university leaders wouldn't mind trying to draw a few kids up north. There were already a few Texas kids at Drake during my time 10-15 years ago. You can definitely draw more.
5) If you have to add a private, I add Denver and Murray. Denver is also booming and I think it's worth adding a bottom-feeder along with Murray if you can add a metro like Denver to the mix. Again, think like University leaders - they'll love the opportunity to plant a little flag there and get broaden their student recruitment base.
EDIT - Also, isn't Denver a very good school overall with a lot of research components? Seems like a big no-brainer in terms of academic affiliation.