butterflies and moths

Sitting in my dark closet and floating things in oil and water has really become my newest obsession. I decided I should work on some of these oriented in a portrait rather than landscape layout. Played around with the colors and saturation this morning. I always am second-guessing myself and know that there is room for improvement. I often let time constraints dictate when an image is done, otherwise, editing could continue for far too long. How do you decide when your image is done?

Done