I'll chime in. Seahawks have always been my favorite team. I did root for other teams in the 70's and 80's as a kid, but not as my favorite team. Just for enjoyment watching the game of football. There are always teams one loves to hate, too, which makes it more exciting when not watching the Seahawks. I did play FFB for a couple of years. Though it was fun and I was successful at it, I stopped playing because of how it started changing the way I watched the game. Just not for me. I'd rather root FOR the Seahawks and against any team that stands in their way.
I have no so-called "2nd Favorite". But, I will say that the other teams I will root for are my 2 youngest boys teams. They've played for 4 different tackle leagues. One will be in high school next fall. The association they played in this spring and will again this fall wears NFL team helmets, etc. It wasn't too bad in the spring, but this fall I'm going to have to say, "Go _ _ _ _ _ _ " for 2 games each Saturday. Maybe I'll say, "Go Blue" or something like that. It will be worth it because they will be playing for a more elite team. (There are no Seahawks teams anywhere in our area... or we might move in order to play for such a team.

) My younger son (who was the star RB for his spring team) understands the difficulty. He's thinking of putting a Seahawks logo on the inside of his helmet or something like that. He actually asked if he could wear Skittles cleats! Even the mere sentiment for him to say such things is enough to bring a grown man to tears.