To be honest 5'7" isn't THAT tall. I mean, yeah, it's generally taller than average, but it's not like you tower above the crowds or anything(I'm 5'8"). So look at you fav anime/video games and pick a character you really like. As long as she's not extremely small/petite/chibi-like in comparison to the other characters, you can probably pull her off just fine without looking ridiculous. Video games are especially good to look at, they tend to have taller girls rather than cute petite ones(eg. Samus from Metroid, Zelda, Sheik, Midna, ect... from Legend of Zelda, pretty much every girl from Soul Calibur, a good deal of the Fire Emblem girls, many of the Final Fantasy girls, and the list goes on...). As for anime, try and avoid the animes that have an extremely cute chibi-ish style and/or characters. But once you get past that there are tons of options out there.
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