You can't have a 5-letter elfin name. Maybe the human abbreviation, but even that is usually longer than 5 letters. Only existing one I can think of is 'Tanis' and that's short for 'Tanthalas'. Elven names are long. Look at the well-known ones. Galadriel, Lauralanthalasa, Gilthanas, Legolas, Jiriki, Solostaran, Elrond (another halfbreed). Arwen is 5 letters, but she's not supposed to be as big a character as she is, and it's probably short for something much longer with lots of Ls and Ss and Gs and Ws and trilled Rs. Elven names are suppose to be pretty.