Not what the OP originally asked, that's because I cannot put out into the universe the Seahawks losing.
However, I will put a rooting order here:
1. Seahawks
2. Packers: I like Aaron Rodgers and respect his talent. Not to mention he gives respect where it's due and admitted to Sherman he avoided him (unlike the sourpuss "Ya mad brah" Brady who didn't give the Seahawks their due). Plus a good friend of mine is a Packer Backer
3. Cowboys: For the underdog storyline or similar-to-Seahawks-storyline, Tony Romo gets beat up on an awful lot and it would be nice for him to get one up on everyone. Plus respect to the O-line, Dez, and Demarco. Plus in my daughter's daycare, one of the teachers is a huge Cowboys fan. And one of the parents that I talk NFL with a lot is a Cowboys fan. And both of them are super cool.
4. Cardinals: Because I like their Next-Man-Up attitude. And Larry Fitzgerald is awesome. There have been other threads on here about the impossibility of luring an elite receiver to Seattle because he wouldn't be able to get the stats. Larry Fitzgerald would be the one who would fit. Elite AND will do what his coach says.
5. Panthers: Don't really want to root for them. Don't like them. But since Cam had his accident it'd be a nice story to see them make some waves. Maybe a new beginning for him.
6. Lions: I really really do not like the Lions
In the AFC, I might be unpopular in my opinion: I'd root for the Patriots and the Broncos. Even though Brady didn't give the Seahawks their due in the "Ya mad brah" incident (then again he could have been in shock), I do I respect the longevity of Brady and Belichick. For teh Broncos: it's really Peyton Manning for me. For any guy to come back from neck surgery and still be one of the best QBs, despite physical deterioration he is an inspiration on what hard work and preparation and a good mind can do .. I would root for Peyton Manning.
So to be clear
1. Seahawks