Sister's boyfriend proposal idea

My sister's boyfriend is about to propose to her soon and I know she won't like some details about it. This will be the proposal: They're going on a staycation in Miami beach, renting a hotel for the weekend, one of the nights they are going for drinks at Bayside, which is a shopping place right by the water. He's planning on doing it on a pirate ship party boat, which is a tourist attraction, as soon as they get on board the song "Casate conmigo" will start playing and 30 of their family and friends will pop up and then he'll get down and propose then we'll all set sail for the night. Pros: She likes Pirates of the Caribbean, it will all be filmed, she loves dancing Cons: I know she doesn't like party boats, Everyone has to pay an entrance fee (around 30 each ticket), Its a cash bar, there will be around 70 other random people there, I know she'd want more family and friends there, seems a bit impersonal :/ I know my sister deserves something super special and romantic, even my parents are a little hesitate about the whole thing. Is there anything as a sister I can do to better the situation?