To be honestly, I hate that being "fiery" is seen as a good thing, or even a neutral thing. It's one thing to have your players' backs or to motivate the team; it's quite another to act like a baby on the sidelines and get into altercations with other coaches. He might be a good strategist, but so is Rex Ryan. A coach acting like a fool all the time eventually leads to players to lose respect for him. Harbaugh's had great success so far and is pushing all the right buttons, but so was Ryan two years into his tenure. It can fall apart quickly. Stacked rosters can show major weaknesses in the span of a few weeks.
I think the 49ers will progressively get worse over the next two years (it's kind of hard not to). I think they could easily miss the playoffs in 2014-2015, not even counting a major injury.