Morning there Rob,
You have definitely captured the data. Though the image is red shifted quite a fair way hence the brightest star there is actually a Yellow star, and the main neck of the swan is actually a white nebula (very strange

)
What processing software are you using? Photoshop?
If so have a look at your histograms and just for a bit of a baseline look at what colors you are aiming for do a auto color then stretch the bejeebus out of it. This isn't how to process this is just allowing you to see what data you have hidden and a rough color balance. I liken it to focusing you don't know if you have achieved the best focus till you have gone past it then come back to sharp focus, don't be afraid to see whats on the other side because you can always come back!
My work flow generally consists of iterative levels gradually expanding the histogram to fill the full 16bit gamut. then followed up by using delicately placed Curves to start really pulling faint data out while suppressing back ground noise. Also getting your hands on something like Noise ware or Noise ninja just a few that work, will help you with suppressing dark and color noise and smoothen up those subs!
Also what kind of equipment are you utilizing?
Brendan