Doesn't have to be bright white. THere are tons of ways to light a scene to get contrast, color, and depth without having to go fullbright on the thing.
You dont have to unwrap the high poly because all you're getting from it is ray data from the normals on the polygons. You only need the lowpoly UV'd so it can bake the proper normal data on the material sheet. So if you unwrapped the high poly you kinda wasted time but you'll learn from it. If that one IS your highpoly, go ahead and put more detail into it for better normal mapping
Nice job though.
Looks like a good time, and thats all I care about. I dont think blizzard has ever done anything super revolutionary, so its unfair to expect SC2 to be so. This looks faithful to the old one, I remember how much fun the old one is, superb job.