I must admit that this is the feature I liked the least in MTW.
It's adding nothing to a medieval game when the factions you destroyed come back again and again and again...
Annoying, nothing else it was.

For EB I could imagine to implement it for a few particular factions (germanic and celtic tribes for example). But I don't want to see re-emerging AS, Epeiros, SPQR or Quart-Hadast. *shudders*