Now would be a good time to ask this: are we going full native titles and the like? I'd advise against it, because I think it breaks immersion indtead of providing it. The resulting mess and bad grammar of events and general game texts creates an incoherent amalgam of modern languages and Medieval concepts that don't bend in. It's like SWMH, where things like a Hungarian "Hertog" breaks it because someone translated Duke into Hungarian without going far enough.
Of course, that's my opinion, but as I said when we discussed Visigothic culture, no need for a "Theudereiks of X". To me, King Theoderic has a much better ring than Theuden Thewdereiks, and in 1066, it means the same, so it's a bit redundant. One thing is to add titles that English can't really represent or that are already accepted into our English speech. Another one is to fill the screen with babble and foreign words. And mind, I'm not English, but I'm playing in English and I like coherence.
PS: Nothing to do with you, Nemo_XIII, don't think this is a bad response to your post.