See if the following two calibrations / settings help (it worked for me, DTH input, ~400 sq ft room, windows on side). All I know is that we share a fondness of bright colors (vivid or saturated colors being the other as seen in best buy). Of course a lot would depend upon your input and room. You could start with my settings and keep changing few as and when you see a problem, few of the ones I've seemed to eliminate are "nothing visible in dark corners", "jagged edges", "blindingly vivid reds", "blurry hair edges". One week and I am changing yet.

Scene: General
Picture
Picture Mode: Vivid
Backlight: 9
Picture: 90
Brightness: 50
Color: 60
Hue: 0
Color Temperature: Neutral
Sharpness: 0 (all the way down, worked for me, DTH is really good, a lower setting helped me to smooth out jagged edges I started seeing upon setting a higher sharpness level)
Noise Reduction: Off
MPEG Noise Reduction: Low
Motionflow: Standard
Cinema Drive: Auto 1

Scene: Sports
All general (non-advanced) settings same as set in General scene above. (Maybe Motionflow: High, keep all Noise Reductions Low or Off in that case, dunno why they cause a visibly delayed blurring).
Picture>Advanced Settings
Black Corrector: High
Adv. Contrast Enhancer: Medium
Gamma: 0
Auto Light Limiter: Off
Clear White: High
Live Color: High
White Balance: All 0s.

That a picture speaks a thousand words, it better be crisp to my tastes... Happy viewing.