Very nice Paul, I like these wide fields shots. Have you ever thought to add some diffusion filtered exposures to the wide field subframes? I used to do it for a while and to me the final resoult is very nice. Here is a link to some notes I wrote on the matter long ago:
http://www.astrosurf.com/lorenzi/articles/diffusion.htm
Just a suggestion to increase color saturation on the main stars and reveal patterns of constellation. You can see some examples here:
http://www.glitteringlights.com/Imag...258309&k=JzjYV
Clear skies
Marco