All cameras ARE very well usable out of the box. But what you call "I want camera out of the box to be usable." is a restriction that might fit you but not others. Customization of buttons is a huge advantage for all!
If there are dedicated buttons for all options like on 5D and then i can customize, I could not agree more. But here we have bare minimum buttons that we need to delegate customizations or ... put back ones that were default on all cameras with price of loosing other also important ones. I dont consider that progress or advantageous.