Something I loved in the book but the film skipped over was all the bizarre parts of the fight at the ministry because of the strange magical experiments being conducted there. This is what I'd love to see this ride focus on, and not just death eaters firing coloured lights at the vehicle. I want to see the depths of the department of mysteries, especially the time room, they could do something incredible with that.
Credit to Universal they did manage to capture the book details (that didn't make the films) well with Diagon Alley, so I can see them taking this approach here.