I could never see Kairi as a speedster tbh. We've seen her run a few times and she's always been...kind of sluggish. And awkward. Dear God is her running awkward. If we ever do play as her I hope they change that, other wise I won't be able to stand it.
Kairi would however make much more sense as a speedster than as a brute though. Sora already has shades of this with his emphasis on two-handed strikes despite his slender build and it looks sometimes ridiculous. Kairi has a an even more slender, fragile build than Sora (and I'd argue even more than Ventus, who is certainly the most skinny and "lightweight" character out of the Keyblade Wielders so far due to him
literally being a speedster).
People actually suited for "brute" style, which requires a lot of physical power, beside Terra would actually be only Riku, Vanitas and Lea. The first two of those however have a style more akin to a Paladin (Riku) or a Dark Knight/Blood Knight (Vanitas).
Lea is an interesting case but I doubt he'll adopt a brutish "Terra-esque"-style due to what be saw of him before he got a Keyblade.
For Lea, I can actually see his style being a mix of Ventus' and Riku's, not as speedy as Ventus, but with more powerful hits and not as powerful as Riku, but faster.
And of course much inclusion of fire magic in some form.
Back to Kairi though:
The main issue with Kairi is to give her a style that while it
can be a mix of different styles already known, it should not be too similar in the end to either Aqua (magic reliance or "feminity") or Ventus (speed, light reliance).
I've even once thought about giving her a mostly "block-and-counter"-style like Exdeath has in Dissidia, only with even more magic and less Keyblade slashing involved and better speed than the old sluggish tree from Dissidia.
A nice additional spin on the issue might if she can even block and counter attacks made against her allies in certain circumstances, although that may destroy game balance if she's a party member I fear.
You guys are right about Namine, it would suit her to just remain moral support. I was still curious about her potential to wield, so that's why I asked.
A fencer style eh? I could see that. Of course anythings better than the first time she swung a Keyblade....and yet she managed to take out that Shadow with just one swing. Not bad... Hax.
Like said, in
theory Naminé should be able to just like Roxas, but in
theory each capable heart in the universe can get a Keyblade as well and despite some people saying it's uniqueness has been lost (when there were already several Keyblade Wielders even in KH 1) the Keyblade is still pretty rare when looking at the whole KH Universe. Maybe 1:100.000 people might have one.
I had that idea somewhere last year when rewatching Star Wars Episode II: Attack of the Clones and read the corresponding novel to it where they describe Count Dooku's fighting style in more detail.
I thought it'll fit Kairi since such a battle style has a certain vibe of elegance and "class", fitting to her status, it doesn't take so much stamina (because you make only very precise and effective movements) which Kairi apparently lacks a bit and we haven't got one with that style yet.
One might argue Pete and the Beagle Boys in Country of the Musketeers, but these aren't really main characters or Keyblade Wielders.
I tried to imagine namine wielding a keyblade and taking on the 13 seekers of darkness. Couldnt do it. As ech0 7 stated above me, i think its best if namine remains a character for moral support. A warrior just really isnt in her nature.
Naminé certainly isn't a fighting type, never has been. I dare even to say that out of the major original characters, she's the most fragile both physically and by nature. I've always imagined her more like a character who'll stay at the main base and provides mission control and information to the others out in the field, like Yen Sid does.
That said though, I once found a fanart with description of Naminé (where she was wearing a silver-colored "black" coat) and fought with an literal "chain of memories" from afar, disarming her opponents with the chain and somehow freezing their weapons in order to stop the battle instead of actually hurting them.
EDIT: according to the wiki its 7, so that means one of them will have to not make an appearance again (probably terra)
You don't need to be one of the seven shards of the X-blade in order to participate in the final battle or to reappear again.
We have five people already available: Sora, Riku, Mickey, Kairi and Lea.
Seven more people are slated to be rescued by Sora: Aqua, Terra, Ventus, Xion, Naminé, Roxas and Ansem the Wise.
While not everyone may participate in the final battle (or being one of the seven lights) it doesn't say anything about their reappearance.
In fact, Terra is right now trapped on the side of the 13 darknesses so either Lea, Kairi or Roxas will have to fill in for him at least for the time being.
Oh, and I almost forgot them, but Donald and Goofy will most likely also still play a role in the finale.