CE simply doesn't have the nobles to replace the northern realms. I would imagine that the terms will include things like placing trusted Empire nobles in ducal seats and council positions. They can essentially take over control of the realms, without recolonizing.
This is very interesting. I always like reading perspectives of other sides.
Its nothing like that. I'm trying to figure out if its better or worse though what they want to do. Frankly, they should have sent terms days ago, but whatever.