It s a bit early, I know, but what about an expansion with 30k armies (mainly imperial), but nevertheless?
It would be so nice to have the pre-heresy traitor legions+ Primarchs/special characters, and with the current elite system they would be easy to implement.
It would offer a ton of skins and new abilities, not only for sm, bu talso chaos/orks/eldar.
Imagine leading the thousand sons with Magnus+Ahriman+Amon into battle.
Also, the legion specific traits could be chained to the elite characters/primarchs,
Heck, even the Emperor+Conastantion Valdor+Custodian squad/Malcador would be possible.
What do you think?