Celtic Heroes

Depends on how quickly you can get into a top clan, and how long it would take to get geared. Before 120 the mage gear doesn't matter a whole lot, but afterwards you'll definitely want to be swapping those crappy regen lux items for grand or higher rings, aggy grim and braces, etc. Without those you won't have much fun leveling. Whereas for rangers, there is always nice lux gear comparable to high end raid gear. So if you can join a top clan at around 150 I'd say go mage, since you'll have op gear the whole way to 220. If you can't get geared quickly then definitely go ranger