Ideally what you want is a display that does internal calibration so that you’re not depending on the lower quality calibration produced via curves in the video card. The NEC PA series are quite nice and reasonably priced for this. There’s also a number of Eizo displays that support hardware calibration. And there’s also the HP Dream Color. The other thing these displays enable is they can constrain their gamut to that of Rec. 709 primaries.
Apple Cinema Displays are problematic because there’s no way to independently set white and black luminance, so the dynamic range is something you’re simply stuck with. And that means you’ll need viewing environments that are each slightly different to account for the difference in each display. Further, their gamut isn’t exactly Rec. 709 to begin with. This can be dealt with if the application supports ICC profiles or 3D LUTs to compensate for the display, but of course if the primaries of the display are less chromatic than the standard, there’s simply nothing that can be done to enhance the chroma of a primary.
Dark images on screen implies viewing conditions that are too bright. Improper whites means a white point (color temperature) that hasn’t been properly set. There are a number of products that can help with this, the X-Rite i1 Display Pro is quite a nice instrument for this purpose.