Will you be doing the wings as well, they might give you an opportunity for more contrast?
I was actually considering this, and was playing around with various color schemes. However, I found that the small points would give a better contrast, so I based the rest of the model around having the contrast focus on his eyes and the gold armor.
As such, here is the finished result:
He became a bit darker than originally anticipated, but overall I like it. In my opinion Tzeentch models quickly become almost too shiny and cartoonish, which is what I wanted to avoid. The blade was made to be dark metal, with the runes trying to shine a bit. I will admit however, that I have alot to learn about shading and grading on metals - It's damn tough!
In the end, I like how focus his eyes and armor gets with this color theme. The wings became a dark grey mixed with turqoise (as can be seen on the right) and his bones became grey with lighter highlights.
Oh and I tried a few things with the chest-star to emphasize it. In the end, I decided to leave it be as there are already enough things on him to take attention, so I dropped this under the "kill your darlings" category for now. Maybe I will change my mind in the future and re-do that part.
Overall, quite satisfied with my first blue themed Daemon prince!
Oh and thank you all of you for your feedback. Many things on him got altered thanks to you, so I hope you will follow this project log and keep giving those awesome feedbacks!
Next project will be a Helldrake, which is also going to contest for Octobers painting competition
As such, I won't start it until I can make that proof-of-priming-on-date shot.