One way of controlling the luminescence values on your image is by creating a Black and White adjustment layer, and setting the Blending Mode to Luminosity. Then use the sliders to control the darkness or lightness of each color.
When using any tool you can quickly switch to the Move tool without switching tools by holding down the Ctrl (Mac: Command) key. When you let go of the key, the tool you previously had selected will return.
If you would like to select all your linked layers at the same, you can right-click (Mac: Control-click) to the right of any linked layer thumbnail in the Layers panel and choose “Select Linked Layers“.
Hold Shift To Create Straight Lines and 45° Angle Lines