I'm gonna go on record as saying that I've loved the concept of Maniac as a Byronic Hero ever since I saw the WC movie. For all its shortcomings, this is a facet that makes it enjoyable.
The Todd Marshall depicted in the movie is a lovable guy, and he's a good friend to a young and insecure Chris Blair (take the actors themselves out of the picture and focus solely on the characters themselves). He's a genuinely likeable person because he's good-natured. He wants to have fun, and he cares about other people. On the mischevious side? Sure, but not maliciously so. The whole affair with him is tongue-in-cheek.
Bam!, he screws up and gets Rosie killed. You watch him begin the stages of grief, but you also see him questioning himself. Of course, one could take either side of the story, for him or against him, and you can sense that he's teetering back and forth himself, wondering if life just threw him a bad pitch, or if he was truely irresponsible and to be blamed for Rosie's death. That, and having to deal with everyone most decidedly taking the side agaisnt him (Except for Chris, mind you).
If you'll notice, aside from the rescue scene with Blair and a brief appearance or two, his role in the movie is essentially done with. When we see him again in WC1, he's changed his hair color, and somewhat assumed a new personality. I think these changes speak volumes.
For one, I know that the hair color thing is a cheap shot, all things considered, but let's take it literally for a moment. If he dyed his hair that color, it would seem to be indicative of an outward manifestation of an inward change. He obviously decided to give himself over to the "maniac" label, most likely because he's decided that Rosie's death was indeed his fault, and he's trying to be someone other than himself, whom he by now despises. He speaks with a dark tone to his words, and sinks himself into the only thing he can really get any satisfaction out of: flying fast and killing cats.
If you look forward into WC2, his appearance shows that the ten years haven't helped him much. (Bear in mind, I've not read a lot of the extra sources that people cite, referring to him being locked up, or having been married. Where can I find those, by the way?) He obviously is still trying to define himself as The Maniac rather than Todd Marshall. His experimentation with drugs is apparent if you look at his eyes, and that would read as a textbook tell-tale sign of self-hatred in a situation like his.
Of course, there's always the bravado he puts up. The ever-confident Maniac, who flies fast, kills cats, and impresses the ladies with his war stories (and I'm sure that it actually worked at some point, possibly often, but never on-screen).
However, by WC3 his years are finally beginning to speak to him. He seems to have come away from the drugs (which, I realize, is coincidence, but, hey, what's the harm in taking things on how they appear?) and had allowed his appearance to level out some. In short, he's matured a bit, but still clinging to his persona, which is, by now, so engrained into him that he himself believes he truely is who he says he is.
This causes him to be baffled, however, when he's passed over time and again for the promotions and honors he so obviously "deserves". Again, he's believing his own tale at this point. "I'm a war hero! I'm the best pilot in Confed! Why am I not getting the rewards I'm due?" Hence, his extreme bitterness towards his old friend, who has excelled greatly.
I think that, during the peace time between the end of the war and the Border Worlds Conflict, Maniac found a small amount of validation in the fact that, with Blair in retirement, his (seemingly) only roadblock is now out of the way, and he is now THE best pilot in Confed. In the TPOF novelization, Maniac even seems to be genuinely surprised that Blair has let himself go during his time away, and is now vaguely able to keep up with Maniac in terms of skill. I think Maniac found more validation to his persona in this, and that is why he seems a bit less bitter towards Blair, and even chumly when the situation calls for it. It doesn't, however, bring him out of the Maniac persona, and so his behavior in general is still the same. We also see, in the game, Maniac trying to pass on his "wisdom" to younger pilots (Troy Carter, to be specific), hoping that maybe he can do something good in the face of all he's done wrong. The downfall of Catscratch (be it death, or just a good chewing out) brings him into a sharp realization that his "wisdom" will only get more people killed.
By WC Prophecy, I think Maniac has pretty much resigned himself to his fate. Luck has been with him, but he will eventually, inevitably, die. He's resigned himself to the death nature of his job, and therefore chooses to live out his bravado to the utter end. Age has only tempered the edge of his knife, so to speak.
Ultimately, by clinging to Rosie's nickname for him, Maniac uses this dark, dangerous persona to hide from the fact that Todd Marshall was the guy who screwed up too much, and got people killed.
(Sorry for the really long post. I've thought about this topic a lot, and thought I'd just dump it all out there in one big essay.)
Then again, maybe not... (actually, writing Maniac's autobiography would be a good fan project.)
