
click to enlarge somewhat
It's not very painterly to put black holding lines around objects. That device comes more from the world of illustration and comic books.
There is nothing wrong with illustrations and comic books, though, so in the right settings, black holding lines are very cool. (and yes, I was a Patrick Nagel fan)
I think an improvement on black lines can be dark lines of the same hue as the color they are surrounding. That can be a nice look.
I was struck recently by a twist on the theme I hadn't noticed before: a hybrid between holding lines in some areas and none in others. I think this illustration (above) is pretty effective in conveying depthby using dark holding lines only around selected foreground elements, and pushing the background into the atmosphere by color choice, and by not trying to outline the background objects.