If the ending point for the SEC & B1G is 24 each. I think the next big battle is over North Carolina assuming ND would never choose the SEC. I think both leagues want NC and from comments I have read NC is torn academics want the B1G and athletics want the SEC.
If the B1G gets ND,NC, & Va. and Duke (I could see the B1G agreeing to take Duke to influence NC). That leaves at most 6 spots left from west of the conference to go to 24. Also, the B1G could want Ga. Tech for recruiting but I would see the SEC offer Ga. Tech to block the B1G from going that far south. If the B1G is limited to 6 more teams I think USC, UCLA,OR. and UW are 4. Who gets the final 2 out of Cal or Stanford, Col., KU, ISU(I think the chances are slim)? This is why I think its hard for ISU to get a spot in the B1G. If NC chose the SEC the only possible school I see the B1G taking from the ACC is Va. I doubt they take Duke with Va. or NC St. with Va. if they lose out on NC. So then the B1G has 9 spots if Va. is taken alone.
The spots in the SEC on the other hand are interesting if they lose out on NC. I think FSU & Clemson are no brainers. I think they would take Va. Tech and NC St. also but that still leaves 4 spots. I think KU & ISU could have a better chance at the SEC in this scenario. There are no obvious picks for the SEC final 4 schools. If the B1G got most of the academic additions the SEC might want to elevate its academic profile, ISU & KU are two new states and they fit in well as geographic partners for Missouri and OU. Even though ISU is playing very good football right now, long term the SEC might want some perceived easier wins for their schools.
Some ISU fans that really want the B1G might think this is anti-ISU which it isn't. The SEC exposure might give ISU an advantage over Iowa going forward with respect to football recruiting. I think the B1G really blew it by not getting OU & UT, they needed access to Texas.