excellent.. yeah that made a huge difference for me when I implemented multiple parallax layers.. I have some background stars on 8,8 and some others on 12,12, other "local" bodies at 25,25 etc.. took a lot of tweaking, but its worth it..
that first background looks great! is it a static image? or are you adding dynamic stuff to the scene? I'm building nebulas and swirling gases for each level - I have little pieces and I build them randomly around the map (not the most efficient way I don't think)... and my "radiation layer" is a tiled background..