I definitely had to go more than half way for some of them, also there's 4 parameters for each stat isn't there? Sword Skill + 3 unique parameters. Sword Skill definitely counts towards getting the outfits.
Sorry, yeah I meant all four parameters.
It's either half way or a bit more than that.
It's difficult to gauge the exact requirements because there's no way of telling when you unlock a costume, but I'm certain you don't need do more than half/slightly more than half.
Ok, I have the game, but I don't really get the combat system. I just spam O, occasionally use square, and sometimes L+O. When my partner tells me to use a sword attack, I use L+O but it doesn't always result in a double attack. Then she tells me to stun the enemy, I don't know what to do. I'm fairly certain I'm playing the game completely wrong.
Use EXT Onslaught to stun enemies. That's the square button if you haven't reconfigured your skills.
You shouldn't need to spam circle for burst attacks. It's probably a better idea to auto-attack to regenerate SP quickly and then use one of your sword skills to finish off the enemy. If you want to use burst attacks, be on the lookout for "Just Attacks" so that you can keep your risk level as low as possible.
Your partner might ask for a co-operative attack or ask you to use a sword skill. Depending on which it is, you might not see the cut-in where both you and your partner use sword skills at the same time.
The battle system is fairly open, there's no wrong way of playing the game unless you're auto-attacking everything to death.