1) The map looks not really like a part of a universe, i think mainly because of the borders (galaxies have no borders). Maybe it will help to fade the color panels out toward the outside, instead of cut them. or/and throw some more random stuff in the space when you zoom out, sun, comets, asteroids..
2) maybe faction borders would look nice, if they are discreet (not like in my picture). They would contain only planets that are 100% territory.
3) i think the connection lines between planets can look better, but i don't really know how. Maybe someone else got an idea, with different colors for the lines, or striped lines instead etc?
all no big priority, but would be nice as we will spend much time to look on this map.