Looks like you covered all the bases, though I admit I'm not familiar with Kislev.
And I bring up this next point only because it was brought to my attention when making my sad little mod: Thane translates into Lord so your basic and great leader are essentially the same thing. Maybe make basic leader chieftain or somesuch. It's semantics though I suppose.
You are making yourself one busy, busy person.
But I'm like everyone else here, super excited to see you pull all this off.