If I just kept the outline it would always look like an unfinished tattoo. I feel the shading really made it pop and gave it realism which is what I was going for.
I don't have much experience with tattoos as this is my second one, I just hope if color is added the realism will go away. I will just have to talk to the artist.
Can you add some type of color to it, like a water color paint, to see what it would look like with color? If some type of marker, paint, etc. could be added, then you could see if you like it with color or not.