Choose the one you are most comfy with. (Try them out in PvP. Just get 3000 faction and unlock it.) The dervish has pretty much exclusive access to the Avatar Forms, which are long-lasting, non-removable skills that do things like increasing damage, armor, attack speed, or changing damage type.;
,, Except in very rare circumstances, more armor is more protection, and is better.
 Heart of fury and Zealous Renewal are examples, but check guildwars.wikia.org for more examples.
Get an elite.
Get a max scythe (max is 9-41).

,
Get max armor (70 AL).
Get good enchantments.
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