Radagast, Alatar and Pallando

[Legate of Amon Lanc]

Alfirin, I understand your line of thought, however, at least in my opinion, the in-Middle-Earth logic implies that Radagast was simply "forgotten", so to say. I would phrase it this way - he forgot about his mission and went to "play with animals", so also they forgot to inform him about his boat ticket back to Valinor, as well as about his appointment in the first place. It was not anything "evil" from Valar's part (or Gandalf's, for that matter): he did not even want the boat ticket back, obviously. It was simply like "yes, you decided not to do your duties and instead spend your days with your hobbies, we are not going to punish you for that, but we are also not going to reward you for it either; and after all, you seem happy where you are, so we simply won't interfere, you can stay in Mirkwood and be happy, we are not any enforcers." I think that's very nice and, when you look at the behavior of Eru/Valar in other situations, very typical.

Gandalf could not "give over" any authority of his. His task had been fulfilled. Radagast's task (which was the same as Gandalf's, and that of all other Wizards) had not been fulfilled. He did not do what he was supposed to do. That said, if e.g. some Dark Lord had risen in the future, nothing would prevent Radagast to stand up and fulfil his task then, if he decided that he wanted to step into the arena back again. That is, I think, also the basis for the best (and "canonically approvable") Fourth-Age-fictions. But he seemed generally not to be interested.

Let me use a parable - I think the Istari can be compared to a group of five elected politicians who are supposed to fulfil certain roles in the government. Some of them go to usurp the power for themselves, only one stays in office until the end of his term and does everything he was supposed to do. After his duty is finished, he gets some reward for that. Radagast basically quits his post and instead goes to retire in his cottage in the countryside. There are no obligations for him, he simply chose not to fulfil them. He chose not to do anything.

I cannot imagine Gandalf going to visit Radagast and "giving him over" the responsibility for Middle-Earth for several reasons. First, like I said, Gandalf had nothing left to give. Second, Radagast obviously did not want to be given any more responsibility. He did what he wanted, he did not want any obligations (maybe he did not consciously formulate it that way, but that is what he basically did). And Gandalf - especially the post-destruction-of-the-Ring Gandalf - would not "force" anything upon anybody. After the destruction of the Ring, Gandalf was just happy - at last, after thousands of years. And he also left the responsibility of Middle-Earth denizens (Hobbits with the Scouring and rebuilding the Shire is the best example) upon themselves. He would not go to Radagast and start reminding him of duties the Brown Wizard had forsaken. He would - like the Valar - just leave him do what he will.

[Legolas]

Though it is a pleasant thought, Gandalf would not have handed off authority to Tom, another wizard, or any other greater entity as it would've been contrary to his intent, as well as that of Manwë who sent him originally, and of Eru who reincarnated him after the fight with the balrog.

I feel like this is one of the main themes of the work. With the immortal beings fading into the West, the time had come for mortal races to grow in stature, assuming the stewardship of Middle-earth.

The Valar had tried a full-on approach with Morgoth earlier, trying "to guard and seclude the Eldar by their own might and glory fully revealed" - and well, that didn't end so well. Nor did the blunt measures taken concerning Numenor, where they dealt with Sauron on his own for the first time. This time, they were more subtle.

As above, the wizards were "forbidden to reveal themselves in forms of majesty, or to seek to rule the wills of Men or Elves by open display of power, but coming in shapes weak and humble were bidden to advise and persuade Men and Elves to good, and to seek to unite in love and understanding all those whom Sauron, should he come again, would endeavour to dominate and corrupt" (Unfinished Tales) - that is, not to fight the battle themselves, but to guide the elves, men, and hobbits to handle evil for themselves. If the battle was the wizards' to begin with, they would not have accepted the restrained forms of old men - they would've traveled directly to Mordor from Valinor at full potency and met Sauron head-on.

Accordingly, once Sauron is defeated at the end of The Lord Of The Rings, Gandalf charges the mortal races with the responsibility of Middle-earth in a conversation with Aragorn before he leaves Gondor for the last time:

And Gandalf said, 'This is your realm, and the heart of the greater realm that shall be. The Third Age of the world is ended, and the new age is begun; and it is your task to order its beginning and to preserve what may be preserved. For though much has been saved, much must now pass away; and the power of the Three Rings also is ended. And all the lands that you see, and those that lie around them, shall be dwellings of Men. For the time comes of the Dominion of Men, and the Elder Kindred shall fade or depart.'

'I know it well dear friend,' said Aragorn; 'but I would still have your counsel.'

'Not for long now,' said Gandalf. 'The Third Age was my age. I was the enemy of Sauron; and my work is finished. I shall go soon. The burden must lie now upon you and your kindred.' (VI.5 "The Steward And The King")

[Inziladun]

I'm just popping in to say there's another great thread touching upon a lot of the ideas that have been discussed here.

[Sarumian]

Well, a great thread indeed and I just would like to stress that all Istari who lived in the West contributed to the victory, even Saruman did. Partly his contribution came in a negative way, as his urge for the ring made a tremendous mess and confused Sauron badly enough. As a result of capturing Pippin and Merry by Saruman's uruk-hai, Sauron decided that the ring passed to Isengard and then, after Saruman's defeat, was in the hands of Aragorn - so Sauron sent insufficient forces to conquer Minas Tirith and lost it. And since then The Eye's primary attention was dedicated to the Captains of the West, not to two hobbits in his own domain.

Moreover, before succumbing to evil Saruman was a useful aid to Gondor and Rohan for ages; his role in the White Council was also positive in the beginning.

As for Radagast, he achieved some goals, such as establishing relations with Beorn (which proved to be of critical importance for the entire struggle), watching Dol Gudur and sending Eagles. It's highly likely, he prevented a conscription of any significant number of beasts and birds to Sauron's service.

While the general feel is that he stayed in ME after the War (if he survived it at all), can we suppose that he might have taken a ship to the West before the struggle was over? Can Vallar really blame him that he did not feel he was created for the fight? He went almost against his wish, so why not to go back if he thought, he was of no use any more? Not just elves, but even a maia did once in the past.