I think there are two things than made late-game PoP much more captivating than any of the two Natives. The first one is that the prophecy made it a clear goal to "reclaim what is yours" and unite Pendor under your rightful rule, something that Native only has as a "challenge run condition", basically. The second one is existence of long term goals for this, such as befriending Noldor or getting many hidden places. Honestly, the fact that every faction has so much inner problems that are going on, it just adds depth to travelling through those areas. Like, you know you will get assaulted by Snake cult in Empire, Heretics in southern Sarleon or Inquisitors in D'shar, and it adds so much character to each region that Native Warband lacks entirely and native Bannerlord underdelivers because, while these groups are there, they are so bland that they trigger no interest whatsoever.
For entirety of the 2021 I've been mastering a tabletop RPG, using PoP as a setting. It was unreal. This world has so much going on, that while I had to add detail to expand the experience, it required so much less from me because the world was so rich in the first place. While at first I wanted to explore bits and pieces of every region with my players, the sheer complexity made me stuck in the Empire and it's inner troubles for a long, long time. And just exploring the map, the family relationships, and the fief distibution among the lords told so much story by itself it was worryingly easy to build lore on top of that. In no time I had so much inner conflict that it kept us entertained for entire year. (for example, why there are three Legatus brothers who all own fiefs in separate parts of the kingdom? Maybe they had something in the past that made them hate and disown each others? Or why Rimusk, cunning bastard, owns two villages, one under a dux and one under an emperor? Why Shadowspawn legion base themselves in Cez and can that mean that Cez and it's lord, Kyros Dux, are rebellious against Marius, who destroys old Empire cultural ways and embraces Pendoric ones? And many many more. Other nations also had similarly interesting distribution of characters (Like multiple barons of Sarleon who own only villages and lords who actually have castles) and it makes me wonder if the devs really considered their placing or is it that my mind is just too creative on creating those backstories.)