The only thing that bothered me with Bowser in the Mario movies....
I know Bowser and the others have some differences in personality and character traits compared to their video game counterparts, but one trait that bothered me with Bowser, is the one that he tries to destroy everything, like the Mushroom Kingdom in the first movie or the ENTIRE universe in the second movie. In the games Bowser was always someone who was shocked by the plans of other villains who attempted to destroy the world or the universe, which showed he has standards, where you can become allies with him to stop a greater threat. In the movies it's not like that, which is even weirder by the fact that movie Bowser was even friendlier and nicer to Mario and company in the second movie, helped them and even was about to redeem himself and didn't want to kill them, when it wasn't for his son.