What the hell kind of plasma do you own that requires max color and sharpness? Jesus Christ that sounds bad.
And then you'll probably go back to where you initially had it. That sounds like a really bad way to (unprofessionally) calibrate a set.
At least get something like this: http://www.amazon.com/dp/B000V6LST0/?tag=neogaf0e-20
This is the TV I ended up with in 2009: http://www.wired.com/2009/04/pr_0422_thx_tv/ only paid $800 too.
I think that I have the model right below this. Or maybe I have this one, I can't remember. I absolutely love the TV. You're right, most games do have a brightness setting, but some games don't. I love it when I go into a game's brightness menu, only to find a "adjust your TV's brightness setting until you can only see blahblahblah". Seriously?
Driveclub is my most recent purchase, and it doesn't have an adjustable brightness.