September 1 would cut in college football the worst. There are quite a few that night. As it stands now the season isn't starting until the Thursday September 8th game. That night there is a college game or two but going forward for the most part there is only one or two games each Thursday until the middle of December.
There is something else to consider choosing to play NFL games on every Thursday. Many high schools
play their games on that night too and ratings would suffer.