The Big Shaggy Dog in the North America Nebula (NGC 7000)
Yes, I know it's pink, but I like it.

Wikipedia -
The North America Nebula is an emission nebula in the constellation Cygnus, close to Deneb. The shape of the nebula resembles that of the continent of North America, complete with a prominent Gulf of Mexico.
The North America Nebula covers a region more than ten times the area of the full moon, my image is just a small part of the nebula.

I experimented using different palettes and I wasn't impressed with SHO or HOO etc
So, I tried a ForaxX pallette. It brought out the strong Ha signal.
I tried another custom palette that didn't bring out the strong red signal.
I then used PhotometricColorCalibration to finalize the colors.

The original image(not pink) is made up of the following -
Red: contains Ha, Sii and Red
Green :  contains mostly Oiii and a little Ha
Blue: contains a mix of Oiii and Blue
The stars contain Red, Green and Blue only

Revision 'D' (ForaxX)  is made up of the following  -
Red: (Oiii^~Oiii)*(Sii*0.8) + ~(Oiii^~Oiii)*(Ha*1.2)
Green:  ((Oiii*Ha)^~(Oiii*Ha))*Ha + ~((Oiii*Ha)^~(Oiii*Ha))*Oiii
Blue: Oiii
The stars contain Red, Green and Blue only
I did NOT try to add red or pink to this image, it was there and  PhotometricColorCalibration brought the pink out even more.

Revision E 
This one is a combination of a modified SHO and a ForaxX palette. I think it is a more realistic rendition of NGC7000.
The Oiii comes out in this revision more so than in the previous two. There is a strong Oiii presence in this area of the sky but it is mixed with the Ha and Sii so it doesn't show up as a strong blue.

Revision G
I did more work on the dark areas. The very dark areas near the center really need more hours of integration but I did more work with PixInsight and it seems to be a little better.

I've done a lot of experimenting with these palettes and I hope you find them interesting.
Monty