One of the conundrums I have is not being able to stop an extra day here or there if you find an interesting place because the reservations lock you in to being at a certain place on a certain day.
I've always been a "must have a reservation" girl because otherwise I spend more time worrying about getting a spot than enjoying myself. That said if we found a place we really liked we would just plan another trip to that place. If this isn't the only trip you'll ever be taking you can make a list of places you'd like to return to and target future trips around them.