I don't think his problem was that his personality didn't come out, I think the problem was that the tone and personality he did show clashed with what the site was at the time. I think he tried to bring something akin to a more snarky Destructoid-esque tone to his articles that just didn't really work.
It also likely didn't help that he was basically a freelancer, was nearly never on the Bombcast and never appeared in any video. I believe Jeff has hinted on his blog that the audience's rejection of Nicholson is part of the reason that they had Patrick doing Quick Looks and the like, as opposed to solely doing news stories.
Of course, now that we have stories written with the classic Alex Navarro dripping sarcasm, I'm curious if Nicholson would have fit in better.
That's a shame. The old Podtoid with Anthony Burch, Aaron Lindee, Brad Nicholson, Jim Sterling, and Sports Sarkar was really an amazing show. Those guys just had so much chemistry together. I guess it makes sense that, individually, you lose a lot of the charm. But Brad's tangents about going to the gym and lifting and the injoke being that Brad was the strongest person in the world really went places. Kind of wish those guys managed to stay together, what they had was special. The moment they all went their separate ways was the moment I stopped going to destructoid.