Rainbowduino suggestions

I love the Rainbowduino, but the fact it does PWM in software uses a lot of CPU power and limits the number of brightness level to 4-bits (16 levels). To do video with gamma correction you need at least 12-bits.

Would it possible for the next version of the Rainbowduino to use a LED driver chip with hardware PWM, like these one of these?
focus.ti.com/docs/prod/folders/p … 59461.html

Thanks for your advice.
Next version Rainbow will updata the constant current chip.
We are sourcing a more powerful chip for flash the LED.
Internal PWM function is good for the atmega.
Thanks again