You are right to go with a bold outline and also get the tattoo larger, as this will help it to be seen better. Find an artist the specializes in dark skin, this could make all the difference in the outcome of your tattoo. Alot of artists tend to over work dark skin thinking the more ink they can pack in the brighter its going to be, when infact they damage and scar the skin and also needle stimulation causes the skin to produce melanin which makes the tattooed area darker. Keep your eyes open and find friends with similar skin tones that have color in their tattoos and ask who their artist is.

You should definately look at their book and see what their shade work looks like. Also you should show this picture to your artist and ask them to draw you something similar, you don’t want to get someone else’s exact tattoo.