This is pretty interesting, as it highlights the difference between elven wizards and human wizards. Elven wizards are craftspeople and artisans. Human wizards are soldiers. We haven't met a single wizard who can't fight, but in Laurelorn they have an entire class of wizards who don't fight.
Also, the "gold wizard" he mentioned was probably Stanisława Skłodowicz, the High Wizard of Middenheim.
So I'm thinking: Jades, Ambers, Runesmiths, Hedgewise at the minimum. Ice witches are a nice stretch goal, and we definitely want to pull in a couple of the major houses as well, but I'm not sure which. Maybe some Ulrican priests? Having a major Imperial god/cult invested could be helpful, but Ulrican's don't play well with others, especially if we get the Hedgewise involved.
I'll leave it to someone smarter than me to figure out the "how" part.