This is a good point. How many characters can one person play, and play well? Three characters is relatively easy. Four can be difficult. But actively playing 5 noble characters, and devoting all the effort to them that is truly needed to make them contributing members of the realm, and not just travel drones? That's rough.
Personally, 3 noble is the maximum I can play well. I currently have 4 and I find myself having at least 2 being pure sheeple. I would not create a new character even if I could.
That being said, if someone has the creative input and the time necessary to do it, why not? It doesn't remove anything for me.
