tolgayurdal, I have red most of your suggestion; overall, it looks great and very well detailed, but there are a few things that I think that deserves to be discussed:
1- The Harad outpost idea did not seem so great for me; as a more nomad faction without a lot of technology, I think that a compact building which gatters everything together does not fit. Actually, the standard outpost with 3 building plots would probably feel more fitting, or perphaps if most Harad buildings were built on settlements while the other factions were restricted to Castle/Camps or Outposts, I don't know. Anyway, a compact building with many expansions may not look very good.
2- I feel like the amount of different units in the factions make many of them feel unnecessary in terms of gameplay. For example, with Rhun riders and wainriders, why would haradrim riders be needed? With so many chieftains and with Dragon Warriors, why would Black Easterlings be recruited? Actually, removing this 2 unit types would also be great as this would make the correspondent Mordor units even more unique
Summing up, it seems to me that you attempted very hard to reach each factions' full potential (which is great), but perphaps you have gone a little too far. I think that for such a huge proposal work, some things and features, such as the units I've said above, will need to be entirely cut off in order to make everything feel unique and useful. So, are these amount of different units ALL necessary? Do Rhun NEED an Outpost building? Does Umbar need a Settlement building AND an Outpost? Shriking your suggestion is important to make things more practical, including making it easier to people read it, as it is very big (even though it is very well planned).
Anyway, I'm for your suggestion, as there are many cool elements on it which I'd like to see discussed here and possibly be implemented, but I think it can be polished even more. Best regards!