Okay, so the de-rainbowing setting I used was chubbyrain2(th=3,sft=20) - it seemed to get rid of all the rainbowing in that clip, but of course you'd have to look over the whole file to find out if you need to use even more aggressive numbers than that (and I'd suggest to tune it so you don't use more aggressive numbers than you need since it'll make the chroma look flatter). I don't think you're going to be able to do much about that chroma bleeding - you could have the affected scenes professionally re-coloured, but I don't think there'll be much you can do about it in Avisynth. On the plus side there's not much bleeding in the scene you provided.

Here's a quick script, see what you think. It takes care of the haloing and aliasing (from the deinterlacing) as best as I can. You can't go too agressive on the dehaloing or you'll make a visible haze around the hard edges. You can use inputtype=2 in QTGMC if you want however the anti-alising will work better with the interlaced mode on and there should be a negligible difference in quality (it's negligible in the sample anyway).

#NOTE: Much better script in next post!

orig=avisource("great_white_clip.avi").killaudio()
orig.ChubbyRain2(th=3,sft=20)
QTGMC(Preset="Placebo",TR2=0,NoiseProcess=2,NoiseRestore=0,GrainRestore=0.5).selecteven()
centre=crop(10,0,-10,-2)
centre=centre.BlindDeHalo3(rx=3,ry=2.5,strength=120,sharpness=0.5,tweaker=0)
centre=centre.LSFmod(defaults="slow",strength=120)
stackhorizontal(crop(0,0,10,0), \
stackvertical(centre,crop(10,478,-10,0)), \
crop(710,0,0,0))

# Use this line to compare to original
# stackhorizontal(orig,last)

Good luck!

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