I think you must be a glutton for self-punishment with all of that stippling. Seriously though, I think this is coming along splendidly so far. The inverted version (white on black) looks great. Maybe keep it that way for the whole galaxy version and use the black on white for zoomed views of particular features? Suppose that really depends on how much color you are ultimately going to add.

Have to keep an eye on this one. Got my own itty bitty part of a galaxy map I've been plugging at (indecisively I might add) for a while now. Maybe I'll have something worth posting soon.