Niniva
It's interesting that you say you side with Chuguru because I take what you are saying to actually be siding with me.
Then you've misunderstood me.
Case gets sick when he goes into low orbit, shoots himself full of drugs to handle the pressure, and the only thing keeping him in the story are a group of toxin sacs that will slowly dissolve, destroying his ability to jack into cyberspace in the process. He isn't Alice and the Sprawl isn't Wonderland. He's an ordinary character thrust into an extraordinary plot, but he doesn't handle himself well, at his best, he's
barely holding it together. At his worst, he's either high, or outright suicidal (sometimes both).
Case isn't a super hero, or even a hero in any sense of the word. He's motivated entirely by fear and self interest. He doesn't have any magic powers, and he when he gets the feeling that someone is watching him, he doesn't stand his ground and he doesn't fight. He runs and hides. He's a hacker, but he's outright told that while he was good, he wasn't amazing. He isn't Elminster and compared to Molly Millions (a cybernetic mercenary, not the Terminator, but close,) Armitage (the former commander of, and sole survivor of the Screaming Fist operation) and Peter Riveria (has implants that allow him to create perfect holograms, among other things) he's
easily the most helpless character in the entire story.
So, if he doesn't meet the definition you gave earlier, is he a good character?
I would say yes. He's easily the most interesting, dynamic and relatable member of the cast, and I definitely think the plot of Neuromancer would have been far weaker had the story not been told entirely from his perspective. While I love the entire novel, start to finish, my favourite segment of the story is Chiba City Blues. It shows Case in his element, and defines his relationship to the world around him. He's an ordinary man doing awful things to make his way in a cold and uncaring world.