Ya I really like the model I had a good time painting mine. I don't use an airbrush but I do normally paint in parts. It has been a while since I painted mine but I think I put the entire thing together before I painted except for the base.
I think you would are better off just base coating the entire then and doing highlights then the rest by hand. The front with the gold (on mine) would be mark to airbrush I think.
Here is mine (sorry for the bad phone picture only one I have right now) I am painting my Eldar in Iyanden with a lighter blue so this fits well.
Your paint skills are way better than mine tho so I don't know why I am posting it haha