You also have to keep in mind that space unlike a surface has no top of bottom. So the map would perhaps be in 3D. In a galaxy the 'Dust' you see is actually stars. Each one of which could contain a system of planets and so on. So in a map you are perhaps trying to show navigation between the stars.

I would perhaps reduce to nearly invisible the 'dust' cloud as that is only to show the scope of the map (it's boundry). With in the map itself you have the stars that make up the galaxy. As it's a spiral galaxy you have there is something called the ecliptic which is the position above or below your suns will be as they orbit the center. If you think of your galaxy as a pizza (anchovy galaxy - kidding). The stars could be on the crust but could also be above or below the crust as well. Their orbits around the center may not be eclipitcal but such orbits take millions of years so their current position is rather stationary when it comes to your map.

As such though systems could be in the ecliptic but above or below each other as well as separate from each other. So you may want to include the systems inclination as well as in it's position.

I myself am interested in making a similar map. I like to illustrate locations for my science fiction writing. I wish you best of luck with yours