I guess without really thinking it through I have adopted a challenge to keep me interested.
Set a goal. Once you achieve it move to a new team.
I'm on my second career and I see a pattern forming. After I win a couple of Super bowls with my original team, I move. By that time my coaching skills are pretty good so the following pattern seems to play out in my new cities.
Year one, making the playoffs is dicey but I have 4 times now.
Year two, win one or two playoff games. I failed at least 1/3.
Year three, win the big one. 3/3 to date.
Move again.
I don't like leaving all my projects unfinished but I dislike boring games and seasons even more.