Dear friend, i think there is no the best color of contacts for dark eyes. But don't be upset. What i mean is that every one of us has different likes and dislikes. If you like it then it can be the best choice for your eyes. I have dark eyes too. I often choose the color contacts that can make my pupil look bigger. But I also like other kinds of colors. Sometimes I will choose different colors of contacts according to what I wear or the makeup of that day. Different of them will give you different looks. Hope you can find the color you like soon.
Dear fiend, if you don't have any vision problems I will not suggest you to wear contact lenses to make yourself look more beautiful. Contacts may bring us some side effects. We may get an eye infection for contacts are applied to our eyes directly and work on the most delicate part of our eyes if we wear them with unclean hands. And contacts may cause dry eyes as a most common symptoms. So I suggest you not to wear contacts if you have good eyesight.
You can try the contact lenses with enhancement tint. This is a solid but translucent (see-through) tint that is a little darker than a visibility tint. As the name implies, an enhancement tint is meant to enhance the natural color of your eyes. Colored contacts with this type of tint usually are best for people who have light-colored eyes and want to make their eye color more intense.