It looks good ... I think it would benefit from some larger black areas to remind us of deep space, the color circles is a fine way to point out systems, but they should be connected with names and perhaps flags/heraldry of some sorts. Concerning flares make sure you are on a layer that is visible (ie on top), and I think the "movie" flare is the best one for stars - but play around with them - and dont put the value to high as it will fill the space (pun intended)