Selective coloring is acceptable  when it is subtle. View hand tinted portraits popular in the 40's and earlier to see some fine examples. With the advent of quality color papers this skill became much less prevalent. When revived through airbrush and digital image processing the technique at first suffured from limitations related to the mediums. Many artists with the advances in available tools have achieved results on par with the best of traditional hand tinting. So it comes down to taste and the quality of the artwork plus it's intended purpose. For instance an advertisement for lipstick would have a different focus than a portrait or pastoral scene. View art in it's proper perspective, decide what you like, then make something that suits your taste better than what you didn't like. Afterwards share it with the community and don't worry about opinions too much.

Acck! I'm starting to sound  like I'm stuck in "presentation" mode! I'm going to take a long lunch for sure.....maybe until tomorrow!