Well after dorking around with things for way too long I have done about as much as I could with my almost 9 hours of shots from this past winter and spring of the Great Orion Nebula. With banging on it pretty hard I have managed this:
1576x20s
ISO 400 to ISO 1600
K-3 + astrotracer
SMC A* 400mm F/2.8 ED [IF]
Bortle 5 skies (suburban skies but are as dark as I can get with only a 40 minute drive)
The last 3 hours of images were collected with it being somewhat in the light dome of the cities but it was really my last chance to image it. The images were stacked in Astro Pixel Processor with some initial processing (star color correction, light pollution gradient removal, and sky color calibration). From there it was further processed in GIMP and RawTherapee.