The addition of Lincoln was approved in the last few months, and doesn't go into effect until 2010, (and they have to scramble between now and then to rearrange schedules). So Lincoln makes 12.
Rockhurst would make 13. Rockhurst is squarely in the MIAA footprint. So the approval vote on Rockhurst, my not be on Rockhurst, per se, but rather supporting an eventual expansioin to 14 or 16 and splitting into divisions.
If Rockhurst is approved, look for a dialogue to begin with Drury (in SW Missouri), Newman (the only D-II Kansas school NOT already in the MIAA), and [WHO might make 16 ??? William Jewell ?-planning an upgrade from NAIA and currently applying to the GLVC? or another Nebraska school like Wayne State (NSIC), Chadron State (RMAC), or Kearney (RMAC) ?]
Well, if Rockhurst does get in, the first priority for the MAIAA is to find one football school, that way they've got 12 football schools. Once this happens, instead of splitting into divisions, they'll just schedule exclusively inside the conference, so every team will play each other once without any OOC games, which the conference has enough power schools in fb to get away with this and not have any at-large berths affected. This means that either they stay at 14 and split into divisions for other sports, or they add two non-fb schools to go to 16 and two divisions.
Other than William Jewell (a conference like the MAIAA would rather take established programs over recent moveups, IE you wouldn't see the Big 10 take Illinois State, or you wouldn't see the Pac 10 take Montana if either school announced they would jump to I-A), the only school that you mentioned that wouldn't work is Chadron State. While UN-Kearney is a bit west of the relative footprint, they are on the southern side of the state and relatively close to Fort Hays State in Kansas. Chadron State is clear on the other side of Nebraska, closer to Northern Sun territory, but probably a bit too far West to be seriously considered. I'd think that they would stay in the RMAC, but most of the other schools mentioned would make good sense.