The place that college expansion gets talked about the most is in the Big Ten, since 5 members already have hockey teams. Looking at the 6 Big Ten schools that don't have hockey, I think there are really only two potential schools that could make the jump to the Division level: Penn State and Iowa. Penn State has always been the obvious one because of their success at the club level. They even beat a D1 school this year when they defeated Robert Morris. Iowa is the less obvious choice, but I think it would be a perfect fit. They've already got junior teams and minor league teams in Iowa, and youth hockey is growing considerably. I think it's only natural that they should have a team at the collegiate level as well.
Another untapped region that I think you could see expansion is in the state of Wisconsin. The state has plenty of Division III hockey schools, but only UW-Madison playing Division I hockey. There isn't a huge difference between some of the bigger DIII Wisconsin hockey schools like UW-Eau Claire or UW-Steven's Point and some of the smaller Minnesota colleges that have D1 programs like Minnesota-Duluth, Minnesota State and St. Cloud. If those teams were given the right incentive, there's no reason they shouldn't move up to Division I.
As far as bigger schools that I could see starting Division 1 hockey programs, one that really sticks out in my mind is Nebraska-Lincoln. Obviously football will always be king, but I think it could be like in Omaha where you've got a group of people that love hockey thanks to their USHL team, and people who absolutely love college athletics. There's already a pretty fierce rivalry between the two schools and one that could actually be played out on a level playing field.
The other area that I think could be cultivated is out west in Pac-10 country. There's already some decent club hockey being played out there. I know banking on the fine people of Los Angeles to care about anything is a giant leap of faith, but I think if it was marketed properply, you could scrounge up 4k-5k aspiring movie stars per night. Washington is another potential team that could capitalize on Seattle's long hockey history.
There's a few schools in Michigan that could potentially make the jump. The three that come to mind are Central Michigan, Eastern Michigan, and Oakland University. Central and Eastern are no different than their MAC counterparts like Western Michigan, Bowling Green, and Miami. They've just never shown much interest in hockey. I know Eastern Michigan in particular is on the borderline and has risked getting bumped down to D1-AA in football. If they made that move, maybe they could take some of that extra money and put it into moving their hockey team up to Division I. Oakland U is probably the trickiest of the three. They've shown excellent commitment to their sports, but they've got the problem that the lady that donated all the land to the university made them pinky-swear that they wouldn't have contact sports at the school, so hockey is probably out.
Liberty University also expressed interest in getting into college hockey. One road trip to an opposing school's rink would probably be enough to get them off the hockey bandwagon. I think we'd all probably be a lot happier if they just let that idea go.
There's a few school that have been talked about that I don't think hockey will ever work at. Illinois is a school with a nice college hockey past, but there's just not the interest. They'd never pay attention to anything that competes with basketball. Northwestern has never shown enough commitment to their athletics to ever start a hockey program. A lot of people want the Big East schools to get into hockey as well, but that's probably never going to happen.
The most important question is how to convince all these schools to start hockey programs. The simplest way to put is that the NCAA needs to find ways to remove the ridiculously high barriers of entry for opposing schools. It takes too much financial obligation for schools to commit to something they see as a gamble.
The first way to lower those barriers is by reducing scholarships. I'm not saying college hockey should do this right away. It would make no sense to blindly start cutting scholarships. But if they put out feelers and get some interest from schools, it would make sense to lower the number of scholarships a team can use by one or two. This makes it cheaper for teams to start programs, and helps spread out the talent pool so younger programs don't get dominated.
The other, much more complicated issue is that of Title IX. For just about any program to move up to Division I, they'd likely have to take a budget-sucking women's hockey program along with them. It's not that I have anything against women's hockey, but they've got almost hope of beign profitable, or breaking even right now. There needs to be some way to get that law reworked so that it's doing what it was intended to do, rather than denying potential college athletes the opportunity to play. If anything, allowing men's programs to start up would create more interest for women's hockey and help make the game better and more successful. Instead, nobody is winning right now.