Thanks for the compliments, I am really happy with how the army turned out.
As for how I achieved what I did with the Stegadon, it was actually pretty easy. GW washes! I used those like crazy. Cover the model in one color, for me with the steg it was the foundation stone color (I don't remember the exact name off the top of my head), then I completely covered the model with the Sepia wash. In the end with no other painting the skin comes out looking like that. Finish the model with a little detail work on the scales and other odds and ends and you're done. So basically not including the howda, maybe 2 hours of work.
As for the Cold ones, I do prefer the older models, good thing it was what was given to me when I started this army a couple years ago. This army has for a long time been completely unpainted, only in the last few months did it turn into what it is now.