I would rather not do a FCS team if needed, for a couple of reasons.
First, is money. We don't NEED another team right now. Any FCS team will cost 5 mil up front to upgrade, and their media value is probably worth 250K. That will drive down annual payouts quite a bit.
Competitively. there is learning curve. It will take more than a few years just to be bottom of the MW worthy. I know they think highly of themselves, and good for them. But Sam Houston struggled mightily when they made the jump. They were making FCS championship games on the reg as well.
Oh yeah, their market is tiny. So growth potential is very low.
Pass.
Northen Ill? For football only perhaps. But other than another time zone, they offer very little for a travel nightmare, especially without a travel partner.
Keep things lean. Go for St. Mary's if the PAC doesn't get them. In the future another option may come about that is a better fit.