Oh, God no. Life without the Packers?
If there weren't the Packers, I wouldn't be a fan of football. The Packers carry a sense of tradition and respect that very few teams, if any, have. There isn't a team on Earth like the Packers. After all, what other team in any sport has you being proud of owning a part of it? And think about it. There wouldn't be Curly Lambeau and his "secret weapon", the forward pass. There wouldn't be Don Hutson turning WRs into a legitimate offensive threat. There wouldn't be Lombardi, or Starr, or Hornung, or Davis, or Nitschke or... God, just the thought of it makes me depressed.
Although, if I were forced to choose, it'd be the Pittsburgh Steelers. They're the team I know is closest to the Packers. Ownership (the team is owned by a family instead of one person), history (6 Super Bowls, Chuck Noll, the "Steel Curtain"), winning tradition, blue-collar style of football, and a near-identical color scheme (black and gold, as opposed to green and gold).