Now this is a toughy. Elrond is in the book for only three chapters and makes a lasting impression on the reader, mainly after reading the council. His wisdom, kindness, and charity seem to be already apparent without Tolkien saying as much, he's the only elf who I don't find fault with and wholly like.
Eowyn on the other hand contributes much more to the books. She gives us the internal struggle that she is feeling and this gives us much action. Though I do not like her views on women warriors, I think that her character makes up for her little flaws.
++Eowyn
I guess I could never bring myself to vote for an elf.