My best friend is called
Eve! So this is going to be biased but...
I think
Eve is pretty without being frilly, girlie without being too long and over the top, short and strong without sounding masculine, and simple without appearing to be missing something. I like
Eve both as a name in it's own right and as a nickname for
Evelyn.
Growing up with a friend called
Eve the biblical character barely registers but it would just be like calling a son
Adam - and there were quite a few Adams at my school too.
Just as a little interest note, my friend
Eve had a twin brother called
Grey, which I always thought was a lovely twinset. :)