It can probably be changed in the firmware as it is likely a PWM (pulse width modulation) based dimmer with a MOSFET driver since there are so many discrete steps offered. The thing is they probably can't go too dim without making it look blotchy depending on just how "homogenous" the diffuser is, and the high end should be resistor limited for maximum current just in case the device goes off kilter so it can't burn the LEDs out if they got left on at max voltage/current.
Me being me, I have to ask you guys with the minimum brightness problems, "Don't any of you have sunglasses?"
I know, I know, they stay in the car so you don't loose them...
I wouldn't mind seeing the white on black reversal option on the regular touch too. With broad stroked fonts it might be easier on the eyes. I like the option on my android tablets, but, of course, they're backlit.