Let's take a look at some faces from popular franchises as a way of seeing what people who are good at what they are doing do:
Now, none of these represent particularly impressive art, but they are very well suited to the task at hand - appealing to RPG gamers/anime watchers AND being fundamentally grounded (in design).
this to look at :
Contrast - they all have it by the pound. Even disgaea, which stays away from the dark range, hits you (BAM!) with highly saturated colors that jump without really needing black. It's also about local contrast - most of these go from their brightest to darkest quickly at the places they want you to look - eyes mostly. The quickest transition from light to dark is always the outline, and yours has it in the hair, which is not where most people want the attention drawn.
Consistency - if one tihng is lit from one angle, so is everything else, pure and simple. each line is handled in a similar fashion, or if not, the change is for a reason (FFT has a strong face line and a soft hair line because, well, hair is soft). Suikoden avoids lines in the hair almost entirely for the same reason, using fine strokes where necessary. The colors are almost always from the same palette.
More to follow....