When you have covered your canvas, or at least have covered the canvas for a particular object, you will ask yourself "what is the difference between the object in my painting and the object in the source. The number one question never asked is "what is more subtle?" Artists tend to over define everything - the pattern is stronger, the lines stand out more, the edges are easier to see, the lines between the fingers are darker...
NEVER EVER, define things more; great artists paint things with all the subtlety of real life. Let your lines get lost, do not add "pop" to your grapes.
Simply ask the subtle questions - "do my lines stand out more than they do in the source?" If they do - make them more subtle - do it! Does the glow on her cheek stand out more? Is the light side of the nose more defined in my painting?
When humans look at things, we can see even the must subtle pattern or line, or we see edges that sometimes are not even there.
Check the color, make it subtle.