Greetings from Utah!
So I've noticed that a lot of people complain about not having a proper sized Warboss for their WAAAGH!!!! The Skaven Stromfiends give you a solid base for a larger than large Ork. Throw in some extra bits from your Nobz sprue (I know you have them) and some green paint and BOOM! Proper sized Warboss. I am currently working on the third conversion, but since I don't need another Warboss I'm going to make a Bigmek with KFF (from the Dakka Jet kit), pics to come in the future.
On a side note, after I got done painting my blue Warboss D'ax NiteKrusha (Single-handedly took down an Imperial Knight in his first game back in 7th). This model would have made a perfect Ghazghkull Thraka... if painted black... with an added metal piece on his head. But I've always been an advocate of making your own special characters and just using the rules for another character. I haven't had complaints from people when I play one of these guys with Ghazghkull's statline.
But I hope you guys enjoy and get some inspiration, the Ork codex is right around the corner!!!