Thanks everyone.
I agree Marc, a bit too clipped I think. I wasn't working on my Dell 27" which has great color channels for working on, but this was done on my laptop which overcorrects the blacks. I can see here on this work monitor that in fact the dark areas are hard black
When I ran a deconvolution in CDDStack and final process in PS, It seemed to clip the colors and there was no going back.. I didn't incrementally savethe stages of processing ! Doh.
Lesson learned
One interesting thing I found is that I had a total of 40 flat frames from two nights(20 each) and 40 bias frames as well. When I stacked with the 40 flats frames this caused a light vignetting; yet when I only used the 20 from the first night it was much less aggressive.