That's exactly the point. The characters speak according to their personality, but the English and the Japanese versions are completely different.

Take Minfilia, for example, who's just annoying in the English script, whereas she's a friendly, warm person in the Japanese version.

Alphinaud would be a snotty little boy who grows up a bit and fights with regret in the Japanese, whereas the English makes him sound like an emo full of teenage angst - which might be appropriate if you look at his character model, but I digress ^^

Yeah, the localization team most certainly did NOT localize the characters. They all use the same phrasing, the same way to speak. Not a bit of individual personality there in the Japanese version comes through in the English.