With a 3rd night of data added, here's another process of the Veil nebula.
34 x Ha, Astronomik 12nm filter, modified Canon 450D
28 x SII, Astronomik 12nm filter, modified Canon 450D
61 x OIII, Astronomik 12nm filter, standard Canon 600D
All 4m subs, with flats.

Pseudo real colour created by adding all the above as RGB.

Hubble palette: R=SII, G=Ha, B=OIII
I think this just isn't a subject that lends itself to the Hubble palette.
Also I'm not happy with my processing. I went heavy on star and noise reduction, but that's blurring the fine lines of the nebula too. I suspect this is one I'll revisit again. The noise levels of the Ha and SII are visible stronger than the OIII, so I think I'll spend yet another night on it some time to boost that some more.