You can modify brightness and contrast, that is the very same idea; however not completely off..
I had that very same issue, if your sitting in your car at night and the key is in the ignition all the lights are on, if you want to dim the lights at night you need to turn on your parking light. Well that really gives you away to any one who just drives by; it's not like you leave your car lights on during the night. It is so bright when your lights aren't on, and if you turn it on it would still gives you away. So that was my solution, because keeping it on night time settings makes it too difficult to see during the day, if you dont use your navi might as well
No such thing as auto off, liability reasons with Acura, that is why it makes you press OK; you agree not to allow it to distract you while driving.