We only hired our photogs for about 5 1/2 hours cuz we were doing the budget thing. But I didn't want getting-ready pictures, and they took a break between the reception and dessert party, which I guess not all photographers will do.
If we were doing it now with the restrictions, I would still hire an outside photographer for everything but the in-park part. (Although, frankly, if we were doing it now, I wouldn't even get married at WDW, since being in the park and using an outside photographer are equally important to me.)