this is my opinion, when i first made my mage(it was my first 70) i got told you have to lvl with fire, i refused and did it with ice.  since then talking with people and looking at posts here and other places i see that several people i talked to say ice is the way.  im not trying to pat my self on the back here; i simply believe that if your style and guild supports what you got then play how you play best.  yes end game changes the rules but till then you should have fun and a good guild will support you.  i regularly ask 60+ to help me lvl and any guild that wants to grow will do what it can after you show that you are willing to help others in the guild.  even if they are just starting a new guy and have a high end guy help them they will help you.