Whether it’s the end isn’t what I’m arguing, just the merits of the choice to add ghosts by Tolkien.
As I recall the other Rangers come and one has a line from Elrond saying something like, “look to the paths of the dead” but there was no other mention of this reserve of ghost soldiers before. I don’t recall this idea that the ghosts of those who betrayed Gondor will redeem themselves coming into the first two books.
It’s certainly important that he declares himself the heir, but it could have been done with any group of creatures.
It certainly helps establish he’s the heir, but he does that by healing people, and other ways as well, so you don’t need it.
Again I’m not saying it’s bad, myths look very different that’s what expect from a modern story.