Well, The beauty of doing the coloring digitally is that it does not damage the original art.

With the detail that you have put in this map, I don't think you should sell short your ability to color by hand either. I strongly suggest that you practice coloring for a bit on smaller test maps in order to get comfortable with your style. And THEN come back and try coloring a COPY of this map, just to see what it would look like. If you like that, then do it for real. One thing though, I have found out the hard way (many moons ago), that it is VERY EASY to over do the coloring and that WILL ruin a good map. which is why I said to practice first on a copy before hitting the real one...

I have no doubt that you will be able to pick it up if you have the patence for it (and by the details of this map I believe you do) and having that skill in your pocket will only improve your mapping. Manual or Digital.

Nicely done