Don't forget you can pick up Anniversary celebration badges on site. From there the day takes care of itself. Cast members are always fantastic but if they know there's a celebration that get even better.
Also consider a Disney photoshoot to go alongside your wedding photos.
I know Disney holidays are for families, but if you're happy with it. Book a Disney BabySitter. From what I've heard they are all like Mary Poppins and kids love them and they tend to come with rare and free disney souvenirs for your little ones. Never ever feel bad doing this, often you'll find the kids had a blast too whilst mummy and daddy went on grown up rides and had a grown up dinner.