Really nice job, Danie! My suggestion would be to take a photocopy of the drawing, or several, and use those to try out different options with the colors to see if it's what you want and that way you'll still have the original intact if you don't like it. I can't tell how big the drawing is but if it's bigger than 8-1/2 x 11, you could take a couple passes and tape them together to get the full image.I am doing a drawing for a friend's daughter who was recently married. I did the drawing from this engagement photo of her daughter and her fiancé:
I'm happy with the drawing, but I was toying with the idea of adding some color to the picture, kind of like the technique of adding color to a black and white photograph (see example). Maybe using colored pencils to make the background in greens, yellows and blues? What do you guys think? Should I leave it as is, or add the color?
Oh, and here it is with a little more detail added in, and framed.