Full payment is required, so yes you would need a credit card. The balcony is $59 per person, and includes a dessert buffet. The riverside seating is $59 for adults and $49 for children, it also includes dessert. My understand is, the desserts on the balcony are more upscale- cake, cheese cake, etc. The riverside are more finger food type- cookies, rice crispy treats, etc. Both inculde beverages.
The thing that really makes it "worth" it is not having to spend hours holding a spot before the show. We did the balcony a few years ago (ok, about 10 years ago when it was still $35 a person!). The view was good, but I do like sitting down on the ground, river side, where you can feel the heat of the fire and spray of the water. That is missing on the balcony. ON the other hand, its really special to be one of 21 people out of 60,000 in the park that gets to sit in special seats!