Give us a bit of insight to your capture/processing steps. Is your computer shaded so you can see the screen well, do you crank up Gamma to aid in getting sharp focus, how may Frames are you capturing and how many do you stack, etc. As to tips on colorizing, I don’t, but others will give you some good pointers.
Computer is not shaded. I have to go to a public park to image because I can't do it from where I live so my setup is on the lean side. I have seen people use tubs turned on their sides for shade and I could probably do that.
I have not been adjusting gamma. I usually sweep the focus back and forth until I think it's good. On a related note, for etalon tuning I usually over-tune (error on higher pressure) and back off until I maximize field uniformity. I actually feel like there is a wide pressure range where I see H-alpha features, but the further "off-band" I am the lesser the field uniformity. I haven't used flats for any of my images.
I have been capturing 250 or 500 frames (2 ms, lowest gain setting) and keep the best 20%. One time I used PIPP to crop and center, but I found I don't need to and have stopped using it. I use AS!3 to estimate quality and stack. I use Registax 6 for wavelets. I use GIMP to touch up proms (burn/dog), colorize, and crop. I usually make small adjustments to brightness/contrast.