Well, I agree with the above posts, to choose Yuna's grid, yet it all depends on how you want your character to evolve, so inevitably, the ultimate decision will be for you to decide.

Now that that has been stated...

I don't see any reason to really take notice of the asinine Khimari, since he has no vital position as a fighter, except Mount Gagazet's battle, which is strangely unchallenging.

But, of course, this is my own oppinion ^_^ I never used Khimari... So my view will appear biased, but at least I displayed it