Currently to get a color value with color picker tool, you have to drag it from the color palette and move it over the color you want. Only after that you can copy the color values from color palette, which is very unintuitive and complicated.
Please allow to select color picker with keyboard shortcut, like I in Photoshop and allow to get color value by clicking on it - this way it's possible to copy color exactly from specific pixel.
Also, Photoshop allows you to copy Hex color value directly to clipboard when color picker is selected and you right click on an area in image. This allows to easily get color values for web design.