...Well then.
So yeah, I was going to try and write up another character for the thread (because even if the idea is cheesy as all hell, it has the potential to be loads of fun), but I think I'll just go ahead and back out now.
CJ and Shadowstar have really said all that needs to be said on the matters of logic and inconsistency, but, Prince, that last post of yours is taking it up to 11. You're absolutely correct when you say that the GM's word is law; God knows I've invoked that rule more than a few times myself. However, you do not ask a player to justify their character/ideas, argue with them for half-a-dozen posts, and then pull the "I'm the GM" card.
If you had just told me that the railgun was unforgivably overpowered, I would have dropped it right off the bat.
Presumably, if you had just told CJ that toppling buildings was just too much for a two-man team, he would have moved onto a different character(s). Badda-bing, badda-boom, problem solved and crisis averted.
But instead, you ask us to justify our ideas. When we do, you're satisfied to poke holes in our explanations. When we fill in those holes, you poke new ones. When we fill in those holes, that's when you shut us down! Do not tell someone to defend themselves and refuse to listen when they do; that's just terrible etiquette!
I know that everybody has their own rules and that your style of RPing is probably going to be significantly different from my own, but I'm still hard-pressed to imagine a "fun" game when the GM utterly refuses to listen to his players and their ideas.
Still, you probably know something I don't, and I do hope that this thread ends up working out for you. I meant what I said about the setting being interesting; hopefully you can pull it off.