The run defense is the biggest concern I agree with Shannon but that is an obvious weakness and I would hope the teams makes some adjustments in scheme and or personnel as required.
SF will just play action this defense to death, the over agressive nature will leave them vulnerable in the middle of the field. If the offense starts slow it will be very similar to last year in the playoffs.
The NFC is wide open, right now we are the 2nd best team in the conference, fix the run D and then be consistent on offense.