I think having hot and cold streaks would be a great idea. Look at the Giants in 2007, they got on a hot-streak and won the super bowl. Or the Bucs this year fell apart and were on a cold streak.
I also think that players should go thru streaks as well. Like in my previous example, Eli got hot late in the season and in the playoffs and had a tremendous game-winning drive.
EDIT: Oh but not in a meter, just like maybe in a newspaper or there could be like a little icon by the team when your selecting your game to play that shows if the team is on any kind of streak.