Gday Ken
With the newer pics, it actually does show up the shortcomings! No offence intended... They appear to have good muscular detail... Why don't you do an image search? There are sure to be heaps of pics on the www as good reference...
I imagine the nags would be well maintained, and therefore would have that 'sheeny' finish...
Keep in mind they are covered in hair not flesh, but then again I imagine it would be hard to recreate... The mane and tail are good opportunities to try a different finish (maybe even a more textured look?) to the body...
Put it this way, I would probably remove the mane and tail during building and try a 'fine cotton' or similar to recreate the individual strands...But then I'm a glutton for punishment :-)
How about very glossy eyes? They would contrast nicely in the lids...
The bridle needs a wash applied to make it 'jump' from the surface more...
Just a few ideas...
Cheers
Brad