No, LA nation should be based on Turkish Empire - you know, Janissaries, etc.
Also, assassins will become non-sacreds. They will most probably get banners too.
As for sorcerers of MA & LA - I'm not sure for now, but I think that we should have SOME kind of strong (read: fireball-flinging) sorcerers in that faction. While at LA they should probably be weaker & with less flamboyant effects...
BTW, what do you see in MA faction except weaker clone of EA?