Great to see my favourite DSO imaged.
For noise reduction using dithering is really very good and very easy. Do you use PHD2? If not then just do it manually, moving the mount a good 10-15 pixels over say 3 or more/10 subs.
For the colours other than red maybe try saturating just the blue and green channels. IP and PS can do so.
IP can do some star reduction.
If you want to try cooling I do have a spare peltier box. But it becomes pretty tedious. The cooling isnt controlled so the darks are not always right.
The box adds weight and you need more wires, and a pc power pack. It can cool the camera down too much and with a newtonian I was getting dew on the LPS filter...might be ok on the SCT. As per Gary Honis
http://dslrmodifications.com/rebelmod450d16c.html
Cheers
GlennB
and thanks for the mention