An FBS victory would do wonders in terms of fan interest. Once you beat an FBS on the road, it shows you have the potential to beat anyone, and certainly you have the potential to beat any FCS team at home. This is the very thing that fans love and that's what gets them fired up and in the seats.
That said, with the defense being as porous as it is, I don't think this is going to be the year for an FBS victory. All good things do come in time however.