They turned Mike into a token and Bev into a damsel in distress. Honestly they downgraded Mike’s character so much I rather he wasn’t in it. He went from being the historian/light house keep to background object. I just don’t understand it, when Ben started spouting the history of Derry facts it soured the movie for me. They took a really important character and made him a fucking token.
Beverly literally gets kidnapped by Pennywise and used as bait. Bill has to rally the troops to go and save her. In the book they all fight Pennywise together but Bev makes the kill shot. Oh and the keep the love triangle no one wanted in the movie too.
Upside the kids beat the shit out of the clown, it was cathartic.