Steps to "dark toned' one.
Starting with your washed-out rendering in Photoshop:
— darken mid-tones with the LEVELS tool, increase SATURATION and GRADIENT color diagonally down from the top right: golden yello - to look like my first posted image repairing your original.
— duplicate layer - it appears ABOVE the original layer and becomes active.
— apply the "find edges" filter - you get multi-colored lines on white.
— de-saturate the layer and set blending mode to "darker color" - now you see dark linework over the original layer.
— return to the original layer, adjust saturation and levels to suit.
— Return to duplicate layer, reduce opacity to suit - to about 50%
— viola! But not as good as a cello.
Dwight Atkinson