Hey Tolgayurdal, I love your concepts as they are a lot more canonical than anything I have seen thus far!
But I wanted to add this: I strongly feel the Blue Wizards should be recruitable at the citadel, much the same way as Gandalf and Saruman.
I also feel it is they who should be the ring-heroes as they are canonically the only ones to have knowledge about it.
If Alatar takes it, he could become the new "Dark Hunter" like what Melkor had in the First Age. Pallando could be really interesting and numerous ideas could take shape with him.
Being a Maia of Namo's people, he could possibly use the ring to summon Celebrimbor? And then have Celebrimbor perform feats using the One Ring like he did in Shadow of Mordor/War.
As stated earlier, Edain like to try and ahere to the canon as much as possible. Tolkien basically scraped the Dark Lord Herumor (though I thought this was very creative to use him) the fact is though Morwe, Herumor, and Nurwe should be replaced by the Blue Wizards as the Blue Wizards are canonical.
Lenwe, Morwe, and Nurwe disappear as King Thranduil takes over the Silvan in Mirkwood and Galadriel/Celeborn take over the Silvan faction at Lothlorien. So it is debatable what happened to Morwe, Nurwe, and Lenwe, but the fact is, their people (Avari) mixed with Lenwe's people (Nandor) and created the Silvan and Thranduil and Galadriel rule those people.
So Morwe and Nurwe would most likely not be around during WOTR.