New digital artists always make the mistake of blurring their colours (dont worry, we all did it).
Instead of being somewhat rebellious with your colour, make it crisp to look at. Try and and aim to show curvature in your shading, if you are going for something more arty, go for something a little more gritty. Colour needs just as much attention as the pencils so give your lineart the colour and appreciation it deserves.