I do believe spring football can work. It's a short season at a time of year there isn't much else going on. The bubble concept the first year is smart to keep costs down. Obviously with that move the crowd size is not so much a factor as this is made for TV. As for the TV ratings the one thing the original USFL had was stars. The leagues they have had since were filled with players who never had a career. the last pro team Birmingham had was QB'd by some guy who learned it on youtube. Compare that to the original Stallions who were QB'd by Cliff Stoudt who was the #2 to Bradshaw in Pittsburg. He was on the back side of his career and he just wanted a shot to play before he hung up his cleats. These are the guys you're going to want to target. Guys with NFL experience who are either trying to get back in the league or who literally just want one last shot at the game before they go live a boring life like the rest of us. Plus the original USFL had a territorial draft so all the local players from Alabama and Auburn Birmingham had first choice. I think the main one that we didn't get was Walter Lewis who was the starter for Memphis, and that was only because of the afore mentioned Stoudt. The other thing the original USFL had was some dam fine coaches. Rollie Dotch, Steve Spurrier, Jim Mora "Playoffs!", Lindy Infante, Frank Kush, Mouse Davis, Red Miller, June Jones, Marv Levy. There was a lot of uniqueness to this bunch and they all had different ideas of how to get it done and the result was very interesting.
So far It remains to be seen if the new iteration of the USFL can pull enough coaching and player talent without having to resort to overpayment. But if they can find the right balance and the NFL sees them as a farm system that they clearly need, instead of an enemy that must be crushed, I think the door is open for survival.