Edit: This is mostly a response to the first several posts in the thread, I didn't follow through with the discussion.
I see your point Olleus (I live in a democracy so I don't recognize your title

) but I think that it's dangerous to go too far with that. I mean if you think about it, you can't let every civ do everything the same way (i.e. giving them freedom to do things any way they want) without basically making them the same. In fact, I think that's one of the weak points of vanilla civ - not enough difference between civilizations (oh and did you notice how many mods exist that give religions more flavor, same thing). The UUs only last for an age or so, and the traits are, well just not enough. At least personally, many of my games felt (and even to an extent developed) the same way, not in a turn-by-turn way, but in the larger picture definitely.
Now as you point out, in vanilla one of the beauties of the game is alternate history and so while I still feel the civs could have had more differences, it's not a big deal. Given that all civs are humans, that are essentially the same, it's easy to accept that alternate version of civs.
Warhammer universe however presents a completely different picture. For one, there are many more differences between the civs thematically, i.e. different races and even different existential states (the undead

). The conflicts and the differences are also much more fleshed out and somewhat exaggerated because being a fantasy setting that's the idea (yeah a good story will always have shades of grey rather than black and white, but I think it's better to have "256" shades of grey instead of "65,000", if you know what I mean). In fact, the whole warhammer universe could be viewed as somewhat of an alternate history.
In the end though, whatever my or your opinions are on the topic of (for example) allowing orcs to write poetry, it all comes down to the perception of most players and how it affects the fun factor of the game. When people load a Warhammer mod they do it with certain expectations - one of them is that orcs are savage "people" that would rather stick your head on a pole than talk to you about philosophy. Of course that doesn't mean you have to force them to be at war always, but if I were to open a city window while playing with orcs, and see there an option to build a university I would probably go "hmmm, that's odd *shrug*", and it will probably take away a tiny bit of immersion.
Anyway, that's just my 2 cents (well more like a quarter really

) on the topic.