Time to Insulate the Dome

[cchell]

I'm building a Pompeli-style oven. Plans were a great start - thanks FB - now I'm on to one of the last steps which is to insulate the dome. I've chosen to do an igloo style, my preference is to keep the total size towards the smaller side just for aesthestics, thus I would like to keep the total thickness of the insulation plus stucco down. So I see two choices:

1) Use one layer of insulating blanket, then about 4 inches of insulating concrete, then stucco

2) Use two or three layers of insulating blanket, then stucco (no insulating concrete)

Any thoughts on these two choices? Any alternatives?

PS, picts of the construction are at:
Charley Chell's Photos - The Pizza Oven | Facebook

Thanks,

-Charley