Baron Mordo is black and the Ancient one is a female in the Dr Strange movie, vastly different from the comic. will fans boycott and rage as well? Heimdall is white in the comic, yet black in the MCU. i dont see why race and sex has to be an issue in a comic adaptation as long as the directors and producers think that they can portray the character that they want well. fyi perry white appeared black in a white superman animated movies back in the days as well.
personality wise, i believe that it is up to the scriptwriter and director to how they want the character to be, to best fit the story and to move the story forward in the direction they want to. maybe we do not recognize the heroes we know so well on the screen now, but as they continue to grow and develop as well as go through events that shape them, maybe they will become the heroes we know them to be.
the way i see it, Marvel's take on their franchise is to have a self contained stand alone movies with one or two references to another event, then once in a while have some all star line up come together. DC's way is to create one big story at one go. The nearest analogy i can find is to use empire's strikes back or Jedi returns. you watch just one, you wouldnt know whats going on. you watch from the beginning, you'll get the full picture.
honestly i have no problems with both DC's and Marvel's movies. when i go in and watch, i try to watch without the knowledge of the comics, because i know they will be a burden to me and hold me back. i know the characters will be different from the comics. if they had wanted the exact same character, then might as well get the writers of the comics to write and direct. I'm just glad that we're living in an age where we can see our superheroes are on the big screen.
anyway tim burton's batman also kill so many goons but before nolan, people say thats the best batman movie also