There are some interesting and IMPORTANT things to keep in mind, such as population and life-span. While this wiki says that the High Elven population is around 20,000 that information was RETCONNED by Metzen himself (Head-Honcho at Blizzard). The numbers are far less, less than the Gnomes but no exact amount was given, but you roleplay one of maybe a few thousand survivors of the -worst- genocidal event on Azeroth.
The Wiki also states a lifespan of around 300 or so years, another RETCON by Metzen, still leaving us with no definite answer. The lifespan used ICly, going off of King Anastarien, would be about 2,000 years. Alleria Windrunner is said to have matured and reached her prime at the age of twenty, but still being so young to older elves may have them regarded as children. Their human late 20s last around the late 200s/early 300s, aging is drastically slow and it's been shown that they elves do not appear to "age" literally until around 1200+.
"All high elves, regardless of class, status or upbringing, are addicted to magic, and all have some small proficiency in it. Unlike blood elves who succumb to it, high elves actively fight their addiction and are required to meditate at least an hour every day to maintain personal control. The high elves are not proud of this addiction, and take pains to keep it a secret. Being close to Moon Wells will satiate the addiction, as will the use of certain magical items, though it should be noted Night Elves do their best to keep high elves away from the Well and magical objects that provide the same result are rare." To be noted are the Sunwell Rings, which have the power to block a high elf's addiction with a special enchanted stone set.
"High elves stand slightly taller than humans do. A high elf is usually a little over 6 feet in height and weighs between 100 to 175 pounds, depending on gender. The elves are slim, with sharp symmetrical features, often an exaggeration of perfect beauty. The high elves are uniformly fair in complexion, with white to flaxen colored hair. Their eyes are incredibly intense in color, seeming to glow with an inner light. While many high elves have blue or green eyes (ex. Alleria), violet and red are not unheard of. They are able to see farther, and have amazing hearing. High elves have white, red, orange brown, black, and blonde colored hair and fair skin, most have brilliantly intense sapphire coloured eyes that glow."
"High elves in Stormwind copy the humans' style of long-sleeved tunics, billowy trousers and leather boots. Many High elves avoid wearing red clothing, as to dissociate themselves from blood elves. They have also set aside a day of mourning for high elves to remember the destruction of Dalaran with their human friends."
"High elves who embrace the path of religion take on the mantle of the Holy Light, sharing in the same faith as dwarves and humans. While this philosophy does not penetrate deeply into high elven society, those who do follow the path of the Holy Light are much more approachable than most. Many also take on a druid-like philosophy regarding the world and nature. The difference being that the high/blood elves view magic as being an integral part of the universe, as it was created by the Titans and is as natural as nature itself; the Well of Eternity formed naturally on Azeroth and created the elves in the first place."