Good crack of the whip chris. Some pointers for you in PS
in Levels
there are 3 sliders Black, White and grey.
Grab the Grey one and slide it to the right a few ticks. this will bring the middle to a more natural look. not so much a look of a photo of a photo if you know what i mean.
Have you looked at "match colour" there is a function in there called vibrancy. very handy for getting colour back into your system.
Learn how to use layer masks. it will allow you to leave the edges alot darker but bring the central nebulosity out a long long way. Further this will allow you to kind of leave your stars while processing other parts.
Also using a high pass blended layer can give you some contrast and pop of clarity to the image
Keep it up, once you have good data then processing is even more fun!
BM