I don't think timed respawns at very specific dates are a good idea; resurgences happened because of a variety and combinations of factors, not because of some mythical force manifesting itself in 1000 or 1150. We're playing a game that is simulating the dynamics of history; not repeating history itself.
What I mean is we should go back to the old respawn mechanics, i.e.: it could happen anytime if the occupying nation is shaky or unstable - without requiring nationalism though. And I stick to it that the byzantines should be represented by a greek respawn, should it happen (like rome being shaky or greek areas being indeps or barbarians).
I don't think it matters to much if a greek respawn has an obsolete uu or up. As far as the AI is concerned, the impact is generally minor.
Same with Prussia-HRE (or even Arabs-Moors. tho' I prefer 1.9) - there's even less distinction here. DoC civs don't operate only according to this principle. Prussia and HRE need to perform different historical functions and give lip service to German disunity, that's why they're separated.What I meant is that the civ itself is redundant in the first place as it is not a distinct culture from other civs already in the game (greek with roman hats, as someone said).
Same with Prussia-HRE (or even Arabs-Moors. tho' I prefer 1.9) - there's even less distinction here. DoC civs don't operate only according to this principle. Prussia and HRE need to perform different historical functions and give lip service to German disunity, that's why they're separated.
"Resurgence" and "successor state" is a bit different.
Basically, some pseudo-resurgencies were decided to be distinct and important enough in their own right.
See also Mughals-India.
Could make the Mughal spawn more historical by having them spawn in Afghanistan, flip modern Pakistan and have to conquer Delhi and and their capital moves there when they take it, like the Ottomans and Istanbul basically.
It would be better than basically handing them the entire Indo-Gangetic plain on a platter like now.
Some are more distinct then others, and serve very different gameplay functions. And respawn mechanics would work for Byzantium, Prussia and Moors fairly badly. There's a reason why original RFC rarely sees a Byzantine-like Greek respawn or a Prussia-like Germany respawn. It's like starting a campaign to represent the USA by removing their civ, stating that the Independent Cities/Stability mechanics is good enough. After all, we already have a secession mechanics, why have a scripted one? The answer, of course, is that Independent Cities would not represent the phenomena that is the USA with an acceptable amount of historical flavour which is worthy being represented.All resurgencies were distinct from each other, so I guess I'll stick to what I said before: the respawn mechanic handles that pretty well.