I voted for Chibi-Usa. Her hair is adorable, even if it's unconventional. Also, as a grown lady, she's quite gorgeous, and you can't beat Princess Small Lady Serenity. After Chibi-Usa, I'd say...
In Sailor uniform: Sailor Saturn. (The brooch and sleeves are awesome!) Also Cosmos.
Out of uniform: Usagi, especially if she braids her hair.
Non-planetary: Vesta and Iron Mouse.
Non-senshi: Human Luna
I am the Titan Soldier of Stars and Destiny! Protector of the innocent! Defender against evil! And invincible! SAILOR CRONUS! Enemies beware-- for your fate is sealed!