Example : I have a friend who has been playing WoW (yes another WoW reference, shocker) for around 2 months on one character and is around level 40. He has multiple characters and from what I understand playing with each is VASTLY different from playing with say your Monk and Warrior through identical missions over and over. In WoW there is such a longer span of time to get level 60 and then once you get there you aren't done! You continue on for a long time and get to some of the real fun stuff. Now the reason the level cap matters is because since we are so low we can't raise it much higher than our own level or else we are screwed. The level cap also ties into group maximum's of 8 and towns and outposts as opposed to a never ending world. We can't take 200 alliance members to kill this level 50 boss (Keeping our cap at 20) which also makes it tough to implement much difficulty.
I personally don't believe that there is any "Young factor" as far as the actual game play difficulty goes (ask me about game play itself and how youngsters fit in there for a different drawn out story) I think it has to do with poor game mechanics with Guild Wars, but can't complain because we aren't paying monthly

My tip - Try WoW or some other Monthly fee'd MMO.

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