You've thrown every filter at it Alex!
Out of curiosity, how were you mapping the SII, Ha and OIII?
I'd guess that you're going for the SHO (RGB) palette with the green tinge.
What you could try when you get a chance is:
L+Ha as a master luminance
R+Ha+SII as a master red
G+OIII as a master green
B+OIII as a master blue
This could approximate an enhanced RGB image
