Some of the best film franchises came from the 1970s and 80s: Terminator, Die Hard, Star Wars. All of these films won the hearts of fans from across the globe, and all of these films also had rather disappointing sequels released years after the originals. Terminator 3 was pretty poor, especially following the massively popular Terminator 2; Die Hard 4.0 wasnt too bad but still was nowhere near as good as the films in the original trilogy; and lets not get started on the Star Wars prequels (they werent very good). So many sequels that are made years after the original film end up being poor, often because a new writer or director comes in or because the tone is changed to appeal to new, usually younger, fans. If Ghostbusters 3 changes in series formula too much, it might just lose the spark that made the first two films great.