Nier brings up some interesting thoughts about character design. I imagine game designers are in a slightly difficult position in this regard. If they keep to the standard formulas they may be accused of being generic and promoting inappropriate gender stereotypes. But as soon as they try something different the "weirdness" of a game's characters may reduce its popularity. I happen to like weirdness, but my opinion doesn't have much relevance to financial success or failure.
Nier actually manages to fall into both of these categories at once, with an odd mixture of original and generic. It is not exactly an achievement I admire, but I do find it fascinating.