WOW, Manual guiding for 180sec X 30 times. Nice image but the background is a little green. I have had a little fiddle, I hope you don't mind. I just pulled the green and blue histograms back to the left edge to balance the 3 colours.
Yeah, I tend to manually guide these days as too much hassle with laptops/cables/condensation with autoguiding. Once I drift align I immediately up and going and only need to make a correction about every 3 minutes. It does mean sitting down in the same position for a long time. I also feel I have contributed more to the photo knowing I have guided during the data acquisition.
I have reprocessed the image again as it is one of those images that you know there is more in there to get out. I have toned back the green also.