Yes, I get that. What I'm saying is that what you (or anyone) wanted from the film is not indicative of the film's quality. If I wanted Two-face from the Dark Knight and I was disappointed by his screentime in the film, that doesn't mean the film is bad. It just means, as I said above, that my priorities are different.
Although this is a bit irrelevant, TDK had good writing because its story was interesting, complex and had provoking themes. The Joker was interesting because he moved the story forward, he was the catalyst. That doesn't mean that any story featuring this Joker would automatically be great.
Plus, I know the 25th hour isn't a superhero film, but I don't see how that matters. Superhero films are first and foremost films, and should be judged as such. Seeing our favorite characters bashing each other's skull wouldn't make a good film. Quite the opposite. Good story, dialog, characters, music, production design, cinematography, pacing, those are what should matter. Any characters used should work to enhance those elements, not be there just for the sake of it, or to appeal to certain people's tastes.
In this context, Venom was needed in the film to be the one character who just can't let go of his need for revenge. He lives for it and it finally destroys him. That was the story all along and if Venom wasn't used, the Vulture would fill the exact same role. Raimi was right in his approach, as he first decided the story he wanted to tell and then used these characters to move it forward. And he achieved that without drastically altering them (Venom alway was revenge-driven), so I think he succeeded.