Actually, such things [rebuilds] can do wonders for the attitude of the team in general. Struggling for a substantial period of time [as we've seen since Drew retired] does tend to get players pointing fingers at both the coaches and fellow teammates especially when you are a champion at heart and see the areas that require more attention from players and coaches alike.
By swapping the entire coaching staff, everyone starts again on page one and no one is guaranteed anything except what's remaining on their current contracts. True, not every rebuild ends in success, nor does improvement happen overnight. But when everyone enters the building knowing that the status quo no longer exists, it has to crank up the attention level a few notches higher now that a new coaching staff will be calling the shots.
The new direction can't be [much] worse than the old direction. That in itself should raise the level of optimism.