I don't know if we'll get the big guy finished in time for Christmas, but we can try.
Do we stick with 10 HD, or follow the "divide by 4.5" rule, which gives us 22 HD? I'm thinking the latter for a unique being of great power.
If we go the higher HD router, do the ability scores (Str 14, Dex 12, Con 19, Int 18, Wis 19, Cha 20) need a boost?
I think Native Outsider and NG will work.