by Ellen DurneyBuzzFeedBuzzFeed Staff If there's one thing about me, I LOVE hypothesizing about a movie casting what-if. Like, what if Matthew McConaughey had played Jack in Titanic? What would the world be like if Reese Witherspoon had been allowed to star in Gone Girl like she wanted? And would Brangelina still have been a thing if Nicole Kidman had played Angelina Jolie's part in Mr. & Mrs. Smith? All very important questions. Well, over on Reddit, movie-lovers have been giving their hot takes on which films they think actually would've been BETTER had someone else played one of the roles.