Godlike
Belial (WA4) vs. Chaos (FFI): Considering I never really voted for Belial, and I voted for Chaos both times, I think it says something about both their halves.
Zog (BoF1) vs. Myria (BoFs): Zog vs. the very person he was trying to summon for the sake of MORE POWER, gee, I wonder who wins...
Heavy
Kanon (WA2) vs. Serge (CC): Serge's plot power is impressive and all, but totally screwed up to the point where I'll say "Trained Bionic Assassin who kills demons for sport" is enough to win.
Zeno (BoF5) vs. Rose (LoD): Zeno's pretty badass, being more powerful than 10 of her flunkees *AND* a large robot, but...Rose terrorized an entire world for 11,000 years unequaled, and the base of her power isn't that much different in nature than Ryu's, for all that its not nearly to the same scale, but I stand by the 11,000 years of experience thing offsets that part.
Middle
Luna (Lunar1) vs. Mog (FF6): Althena powers and such. Surprised Mog even made it this far, lucky draws for him and such.
Jude Maverick (WA4) vs. Belselk (WA): As far as I'm concerned, Rudy > Jude, since Rudy's got similar plot hype, but is also someone who is effectively a machine built for war and thus much better at fighting than Jude. Now, considering Berserk > Rudy in most cases (let alone how he's > the other Quarter Knights, and Rudy struggled with Ziek), its logical to assume Berserk > Jude. Berserk's pretty nuts in plot power, all things considered. Again, the whole "they only beat him when he was having his power drained!" thing says everything about how strong he is.
Light
Galleon (S5) vs. Hrist (VP1): A recently awakened Valkyrie is still > most generic mortals, even elite warriors, though, Galleon's also got Old Age holding him back some. Proof of the Valkyrie > Warriors thing? Lenneth can easily be seen as more powerful than Arngrim at the beginning of the game, and Arngrim was already pretty much the strongest warrior in his own country, so...yeah.
Jin Uzuki (XS2) vs. Virginia Maxwell (WA3): If nothing else, I'm gonna go with Mediums that get a fair amount of plot hype > Slicing up Mechs that are essentially useless half the time.