The two most important characters in most superhero adaptations are the hero and villain. Call them A and B. The rest of the supporting cast fit into other groups.When you have more than one person in the A-group, who are fighting for the same outcome, I dont see how it can't dilute the other heroes stories.
Gordon and Dent were no less heroes in that film than Batman was (though Harvey lost his way in the end), and they absolutely did not "dilute" the story; it seems to me that you simply put them in a different group because they don't wear masks. It really doesn't work that way. You haven't sufficiently explained what quality Robin possesses that makes him different from these other characters in a way that "dilutes" anything.
I think your analysis of how superhero adaptations are supposed to work is limited and simplistic. Whether a character "dilutes' a story has absolutely nothing to do with whether he's the second hero or the third hero or the tenth hero of the piece; it's determined by how the story is structured and how the character functions within it.
Consider that no competent writer says "I want Two-Face, he's cool!" and shoehorns him into a story where he doesn't fit; they design a story where he does fit. Dent had a purpose in that story; his role
strengthened the story of Bruce Wayne, it contributed, and the same would be true of a quality adaption of Robin. The writer
builds a story where these characters serve a purpose and strengthen the narrative--so that, no, they do
not "dilute" it.
Its not that I cant imagine a way to do it,
It isn't? It seems like what you keep telling me is that you can't see how to do it.
its just that the majority doesnt want to see it so whats the point?
The audience doesn't know what it wants, which is why it's the audience, and not the artist. The audience probably thinks that a lot of ideas are bad, simply because they lack the creative talent to conceive of how those ideas can be made to work. That's why the artist is there, to show the audience what it couldn't think of on it's own.
It doesnt make sense to include him with all the other current pieces.
I am not talking about including him in The Dark Knight Rises, since we already know he won't be in it. He could have been, though that likely would have been a very different movie than the one that appears to be taking shape. I'm talking about a purely hypothetical film.