i think there are a lot of plot points in Tolkien's legendarium where you do not need to change the fact to change the perspective:

- the Elves are a puppet of the Valar, doing their bid in exchange for land and favours in the Undying land. Numenor is even more so a client state - sided with us? you're rewarded with longer life and your own territory.

- while the Valar do not encourage the colonization of the land of the "lesser" races (note: there are "lesser" races) in Middle Earth by their clients - Elves following Fëanor and the Numenorians colonies -, they really do not do much to prevent it. When things go south for their clients, they of course help them survive in Middle Earth through open warfare and pardon almost all of the rebels (so much for not supporting the colonization!). It is not so much different from the US being ostensibly against colonialism but bankrolling France in Indochina.

- they keep their "no direct support, but no condemnation" policy on colonial powers for a while. They do not want to harm their clients when their second-rate clients want to renegotiate their terms (aka the Numenorians wanting immortality) so they call on big boss Eru. In line with their history of not wanting to dirty their hands, but still pursuing their policy objectives.

- when their colonial clients are on the verge of disappearing (Gondor before the War of the Ring), they send CIA political operatives to engineer resistance, coups, and remake Middle Earth in their fashion. My bad, they are "Istari". Those agents have no qualms scarifying the lesser people and getting involved in their politics. I have no doubt that the sole purpose of reinstalling the Numenorian dynasty is to help the war effort (it is well known that internal strife bolsters the war effort), not to replace the current leadership - now quite distant from the Valar - by a man who owes everything to the Valar and their subordinates. He was even raised in a pro-Valar Elven colony! The Dunedain program exists only to have a convenient leader to choose if you want to topple current Gondorian leadership. I mean if, say, the US had hosted the descendants of the Capetian - Bourbon kings of France since the French Revolution and tried to push for France to become a kingdom again under their brand new American-raised kingdom after WWII instead of that pesky de Gaulle, would anyone think it is solely for French interests?

- speaking of which, it is good that Aragorn becomes the King because he was born to become king. Right-of-birth is not a very compelling point. Cheap tricks ("the hands of a king are the hands of a healer!") are used to prop up the new Numenorian regime.

- industrial technology is terrible, because it is direct competition to the nature/magic based technology of the Valar and their surrogate.

- Saruman is beyond help because he chose to get power for himself rather than prop up the Valar client states' power. I guess you can make a point that betraying your bosses is wrong, but is a Numenorian disctatorship (whose leader is put into power by one of the Istari) that much better than direct dictatorship by one of the Istari?

And that's just on the top of my head.