[Man-of-the-Wold]

Even as I still contend that Radagast was a loose end, and Saruman took care of loose ends, it should be remembered even as Saruman had become very wicked and corrupted, that was more or less only a very late Third-Age development.

For most of the Third Age, all five of the Istari were probably quite engaged and effective at doing fulfilling their mission for the better part of two thousand years! That's a very long time, and they were as such "men," somewhat unconsciously containing a Maian spirit. In part because of their work, the Third Age dragged on as it did, and in a sense, their having lost their way and strayed may have been unavoidable.

Saruman's fall is, of course, extremely sad and deplorable, but it is more that of a man, not unlike Denethor, than that of a fallen angel.

That Gandalf remained so focused and true speaks to both the type of Maiar he had been, and the personage who he became in Middle-Earth, as well as the Elven ring he wore.

On another note, even as the Easterlings and Southrons were ultimately more numerous, we are often seeing things through the eyes of Denethor, for which Sauron strategically distorted the view, while Denethor found tactical advantages. Arming, marshaling and maintaining those human nations under his control was no mean feat for a ring-less Sauron, taking thousands of years of long-term work, and presumably it was far from universal. Had the West remained better united during the Third Age, and not picked apart so well for such long periods by the Witch-King, Necromancer, the Balrog, Orc strongholds, and recurrent warfare and growing enmity among men, the West could have remained entirely defensible. Even before the end of the War of the Rings, Sauron had been essentially checked (per chess), and Gondor was inherently very strong, but not robustly organized under Stewards compared to what was possible. So, the decisions of the Council of Elrond and on down were not so much acts of desperation, but really rather wise, sacrificial decisions to rid Middle-Earth of great evil once and for all.

Again, with the The Hobbit on through, we see the final elimination of the remaining parts of Morgoth's direct legacies, because of the ring bearers and the Line of Luthien.