The Big Ten would never ever ever ever take all of those shit programs. The media revenue model is based on how much you can add to the conference. ISU will dilute Iowa's already small population. The State of Kansas has an even lower population than Iowa with two schools. No way the B1G would want them. They suck at football. Maybe there could be something done for Kansas because it would give the B1G a hoops blue blood, but I'll bet the powers in Kansas would overplay their hand and demand KSU go as well, which would be a non-starter. Maybe Oklahoma State could get something done.
Don't get me wrong, I would love to see a realignment where the B1G tosses Rutgers and Maryland out and brings in those 4 teams that you mentioned. I would love to see some sort of 4x4 pod system in a 16 team conference and I'd like to see the ACC, SEC and B1G all adopt that. You'd have the Big 8 pod of Kansas, Kansas State, Okie State, Nebraska. Then you'd have the middle pod of Iowa, ISU, Wisconsin and Minnesota. Next would be the Indiana-Illinois pod of Purdue, Indiana, Illinois, Northwestern. OSU, UM, MSU PSU in the final pod, called the "Real Football Programs Pod."
9 game schedule, you play the 3 other teams in your pod every year, you rotate each of the other 3 pods every year. And then one game against a team from the two remaining pods each year. It would preserve every major rivalry game and ensure that you play every team once every 3 years and I believe it would work out so you would be guaranteed at least 4 games per decade with everyone, sometimes 5. I'd make the conference champ participants floating, so the locked in cross pods form the divisions that set the championship participants. So if the Big 8 pod plays the middle pod and the Real Pod plays the Indiana-Illinois pod in year 1, those would be the divisions. If in the next year, the Big 8 pod plays the Indiana-Illinois pod and the Real Pod plays the middle pod, those would be the two divisions for that year. Etc. I think it would be epic.