Unfortunately with these particular TVs you need to adjust the picture settings individually per input and per input format.
Basically, when you're watching TV press the * button on the remote and go to Picture Settings. There you'll find all the brightness, contrast, color temp, etc, settings. But as soon as you change input source or format, you'll need to do it again. There's no way to set those globally.
BTW, if you have the 65R635, I have the same TV. You can also try low power mode.