IMO, the main issue is fan support. We have a very loyal core group with lots of fun things such as the canon, the Model T car, the "North Texas" chant ... but that core group is too small. Previous administrations spent decades tamping down any enthusiasm for sports at UNT, leaving it an after thought for many alumni. It would be much easier to recruit and high great coaches if we had 25k at each game and a community that really backed the teams.
Suppose we had beat Navy, went on the beat Army, and finished the year with 10 wins. I don't think that would move the needle much for next year. It would be very difficult to have enough winning seasons to slowly build a winning tradition.
Long story, short ... winning at football just isn't important to enough students and alumni.
I will agree with others that having our own Boone Pickens would be a great benefit if they could give a lot and have patience. I just don't see that person walking through the door anytime soon.