Yeah, practice duels would basically boil down to: "Who got the higher initiative?" in all cases except Malleus vs Frenz. That would actually be a pretty interesting battle; it would go three or four rounds at least and it's tough to call a winner. But to me it's actually more of a question of who would win among Daniel, Frenz, and Malleus. Daniel's the only person who can inflict a crapton of damage without being overly squishy and Malleus and Frenz can survive anyone's opening salvo (Malleus's Wax Doll and Frenz's class evo, respectively) and deal enough damage back to kill before their opponent can. Plus Malleus has the possibility of Freezing on his blunt weapon which is a very nasty combo; if it freezes the enemy is screwed because then the hammer does even moar damage.
Frenz does have a +3 to damage every attack and can push that to +4 with his class evo, basically guaranteeing himself damage if he lands a hit, and with his high defense + artifact that reduces his attacker's accuracy he's pretty hard to actually hit himself. (For other party members, anyway. >:3) He also takes -2 damage.
Daniel can attack three times a round with higher attack power and an extra attack dice when he hits and he does have that +2 to hit... He has decent defense, and he takes -2 damage too.
Pierre's kinda tough but he's not overwhelmingly offensive-based. He's probably the most balanced character offensively and defensively, but that kind of cripples him for practice duels since the other (excluding Claire) outshine him in one area or the other. He can OHKO Claire with a Seduction roll though, and he has a pretty good damage modifier and is the only character with a chance to follow-up on a melee strike.
Malleus has high HP, high Defense, one round of invincibility, and small bonuses to accuracy and damage. Plus his warhammer can freeze. He takes -2 damage too.
Wymar's pretty decent for duels. He can negate all damage to himself for one round, autocrit, and deal ridiculous amounts of damage with his magic, but enemies get +1 to damage rolls when hitting him and he has no defense against accuracy.
Greenmoore never has to worry about running out of MP, although he's kind of frail. He gets an extra dice with his water and +2 damage with his fire, both of which can attack twice. Plus he can heal himself with his class evo. His defense is good for a mage. His artifacts are nice; one guarantees +1 to his damage roll no matter how he's attacking and the other lets him turn his HP into damage, which if used with enough power and luck allow him to oneshot even Malleus. He takes -2 damage too.
Claire can attack with subweapon and melee on the same turn, put ice on both for the cost of 1 MP each, and potentially lower her target's ability dodge her strikes by a heft amount for more MP. She burns through it kind of fast, though. Her defense is nice but no better than Daniels, although she can regen health if she hits hard, which she has a +2 chance of doing (+3, but Booty Hunter knocks it down one against all these male opponents). She... also takes 2 less damage.
Popular skill, there...
Zathyran has a good sword, but it's obvious his main talent is his magic. He deals 2d6 lightning damage on a minor success if he hits and can attack three times in a round with it, plus he can supercharge his magic to make it a little more powerful. His only real defense, though, is a 25% chance to negate enemy magic. Nevertheless he has a good amount of HP and MP so he can hang for a few rounds.
What does this analysis all mean?
Nothing. Or maybe later on there'll be some sort of tournament to see who the hell gets the best weapon, armor, subweapon, etc. in the game. >:3