How does level 50 balance arena?

[krrrra]

What EXACTLY at lvl 50 do classes become balanced? and why? I can't think of what they'd do.  Increasing/decreasing damage doesn't seem like it'd do much. and lv50 wont make Blade Dancers resist less? How do classes fall off? Everyone says destroyer and summoner fall off. I just can't think of how 50 changes the game.  I'm genuinely wondering.  So if anyone here knows, or played in the Eastern servers, an answer would be much appreciated