Flavius, I do use your settings from calibration thread (backlight level 5).
I found it most useful one,besides sharpness, still trying to figure this one , between 50 to max.
I think regarding Light sensor, it may be user preferences - we do like to watch our evenings movies in a dark room.
In dark room it seems excessive bright with sensor off, but during the day,when kids watching seems very good with both ON or OFF.
I will play with that for another week-two to make final decision.