There's an artist on Deviant Art that I really like called Emma Sarkela aka "Darkjak". On the train earlier I remembered that she did some really cool monster designs that I really like. Here are some images I found:
I love the idea of having glowing "tattoos" though maybe I could use them for my monster in a different way? I still need to do some revamped designs, but I just want to clarify that this is a direction I am definitely considering. I have always figured that the illuminous look might work quite nicely for the monster, especially if the scene itself is very dark.