Pretty self explanatory title here. Just think of how much game time players would get out of FC3BD if the players were able to 'reset' all of the garrisons in the game after completing it. Clearing out a garrison is one of the most fun things to do in the game, I mean hell, it's that very act that encompasses half of it's game time. Besides, you won't be able to experience your upgraded weapons to the fullest extent without a big garrison to run through using them. And you won't have your weapons fully upgraded until nearly (if not all) of the garrisons have been taken.
This shouldn't be too hard to do I imagine. Throw in a few lines of code, a reset button, and viola... 10+ more hours of game play for everyone! : )
In other words... OH PLEASE, OH PLEASE, OH PLEASE PUT IN A GARRISON RESET BUTTON!!!