well, you're starting I presume, skill comes with practice, and observation, I need as well to run a long way to get to a very good level with pixelling and drawing in general, but what I suggest you to do is to finish all your WIPS, and about colors, is just a fact of knowing about contrast, is about using colors that really makes difference one and another in between. and many people use it, and sometimes it looks good, but everybody must agree that you have to be careful with black outlines, because in allot of cases, they make the piece look not as good as it could...
I'm a learner, and I'm not a veeeery skilled artist, but I hope this can help you in some way...
