Y'all know the drill by now.
Cless: Cless is our main character. He's pretty solidly uninteresting, though admittedly to a much lesser extent than most of the meathead heroes I've noted in the past. Rather than being motivated by the goodness of his heart to do acts of heroism, Cless is more guided through his quest by the desire for revenge against Dhaos, who had his parents killed. This doesn't really lead him to be any more interesting than your standard hero with a one-track mind, of course--he still relentlessly leads his friends along into danger for the lofty ideal of Plot Demands It in virtually the same ways, he just has a more personal and ever so slightly more believable reason for it.
He also seems to be the jealous type when it comes to other people getting characterization. Whenever the idea that his sworn enemy might have some motive for his actions beyond Evil For Evil's Sake, Cless gets all defensive. It goes something like this:
"Hey Cless, I wonder why Dhaos is doing all this. Maybe we should try to think of what he has to gain from all this so we could better know how to--"
"SHUT THE FUCK UP MINT YOU WHORE DHAOS IS EVIL AND THAT'S ALL THERE IS TO IT!"
Mint: Mint is the nice, shy healer of the party. As per RPG Law, she becomes interested in the main character, doubtless enamored by his incredible ability to be an even more boring person than she is. Probably the only scene she ever gets where she stands out is the part of the game when she has to meet up with the unicorn so she can usurp its healing abilities for her own use, and even then, it's more just the presence of a unicorn there that makes the scene good, not Mint. Luckily for her, the unicorn gets attacked by demons and dies, so she doesn't have to deal with any qualms about killing it for its horn. What exactly she would have done had said demons not shown up, of course, baffles me. Perhaps she was going to shyly ask permission to saw off that piece of the unicorn's head.
Klarth: Klarth is an older man (by RPG standards, this means an age range of 20-24) who mistakes literature for weaponry and fulfills the team's vital requirement for someone who actually has a goddamn brain. He both explains the various magical phenomena that they witness and hear about, and usually gives them some direction on what they should do next to keep Cless from just leading them around in circles all day, waiting for Dhaos to show up. Of course, this minor virtue of character is almost entirely forgotten about Klarth, because the only thing anyone is ever going to really remember about him is that he once theorized that Arche would "fuck like a tiger."
Arche: When this jailbait half-elf isn't busy propositioning middle-aged sailors (what is WITH these half-elf kids, anyway?), Arche manages to be a kinda okay character with some actual development here and there.
Chester: Chester is a guy who falls in love with a girl that he doesn't like and joins you later in the game about 40 levels behind everyone else.
Dhaos: Remember back when I made the list of Star Ocean 2's characters, I noted that the 10 Wisemen's creators invented the cheapest cop-out of bad villain characterization ever by including a hidden scene in which it is implied that they might at one point have had some form of reason for wanting to be evil? I take it back. Dhaos has the cheapest cop-out of all villainy. See, for just about the entire game, Dhaos is just your uninteresting, super-powerful evil dude out to destroy and provoke protagonists into killing him. Cless's party continually wonders whether there might be merit into investigating Dhaos's reasons for being such a dick, and Cless continually tells them to shut their yaps, but that's about all you get for Dhaos's development. When you FINALLY get to know what was up with him, it's a small note made, in the ENDING, after he's already dead. You don't even get to hear Dhaos say it--all you see is him dying and saying he wants Cless and co. to know his motives, and then suddenly there's a scene change and you get to hear the heroes sum it up in about 2 sentences or so, and then just move on to other things. I mean, hell, why didn't the game just be honest about it and have Fei or Elly come in, sit down in a chair, and tell me instead? I mean, if you're gonna do a lame post-plot wrap-up scene, you might as well go all-out for maximum cheapness.