The data looks good, next step is to remove the green, any gradients and noise, then tweak the colours etc.
I would stick to working in PI to start with. Then if you need to, final tweaks in PS.
I would do:
1. SCNR
2. DBE (sometimes if the data is really good you may not need to do this, see if it gives a better or worse result)
3. Create Mask for stars and nebula, add together with Pixelmath to mask the stars and nebula then de-noise the background.
4. Use a star mask to reduce the stars a little if necessary. (Don't thing you'll need to but worth trying)
5. Use the nebula mask to smooth, de-noise or sharpen the nebula.
6. Run the Dark Nebulosity script (works very well)
7. Final curves tweaks for colour/ saturation etc.
With any stretching be careful not to clip the black or white points, clipping the black too much will result in the loss of the finer details.