As Queek stated on the WPS forum the 4th Book of the Empire contained background and such, I thought I'd give it a try here aswell!
The Provinces I'm leaning towards is the Northern ones, like Nordland & Ostermark, but a shooty Hochland force wouldn't be bad either.
I'm also thinking of incorporating some Kislev allies, so a Northern province would be the obvious choice. But what Kislevite allies?