If I had to bet money this is what I'd go with. KC is head and shoulders above anybody else in the AFC, even in the entire league, frankly. I'd go Saints from the NFC because they're the most complete team right now, depending on what happens with Brees/Hill going forward. I wouldn't be surprised to see GB in there though. I think Seattle, depending on Dunlap's health, could sneak in as a dark horse if the defense continues to improve and Russ and the passing offense get back on track and the RBs get healthy (that's a lot of if's).
I think KC wins it all in a walk. I just don't think anybody can keep up with Big Andy and Mahomes at the top of his powers with those skill position players.
You are correct. the only people who ultimately end up cheering for a dynasty after awhile are that team's fans. Be it the Bulls, the Pats, or the Warriors the rest of the fans reach a point where you're just exhausted of seeing the same team steamroll the league and want something, anything, different and new. I think as a neutral it's often more fun to cheer for the underdog or the newbie vs the incumbent.