@Shadow: ok, I got your argument now, but in a way it's not really solid enough. Mainly because most Fire Emblem characters have limited animations (usually the normal hit, and the critical hit) when they only use one weapon. Marth, being from the first FE games, probably lacked enough animations to make up a moveset based on him, which is why I believe he was completely improvised, just like Falcon and Fox were, and many others.
Roy, as a clone, was given different movements and the effect of flames to reflect the difference between his sword and Marth's falchion. Since he was from the latest FE at the time, he had more animations for programmers to base his Melee movements on, especially since in his game he actually changed classes and had more attack animations.
I'm 95% sure Marth was programmed in the game first, and Roy included afterwards with similar physics, but with altered appearance for his attacks due to his sword.
Also, if Sakurai-san had taken out Marth instead of Roy he would have had massive disapproval. Marth was arguably the best in Melee, people would've been pissed, myself included.
On an unrelated sidenote, Lynn would have been the easiest FE lord to include, having two weapons in FE, and 8 different [badass] attack animations for them to work with. Also, she would've been so cool to use.
@GC: culture has an effect on everything, videogames are no different. For example, look at games like WarioWare and Rythm Heaven and you can see just how different (and weird for us) Japanese culture is.
Also, like rockerJ said, FE mimics medieval/fantasy styles, which is why we have main characters that are 15-16 years old and look feminine due to their youth. Since Japanese people are quite metrosexual, this was never a problem in Japan, but when the characters came to the US people were more inclined to see such appearance as "gay". Same thing comes up with anime and manga.
@SBF87: compared to Melee, I find vBrawl extremely balanced. When you have people beating top tier characters with low tier characters this is evident, something that didn't happen in Melee. Sure, some characters have unavoidable weaknesses, but the fact that mindgames and spacing are so important in this game means that most weaknesses can be worked around with enough effort.
I think the best proof of this is the Sonic community in SWF. Their work on Sonic's metagame led to Sonic's rise from low-tier to mid-tier.