Better question instead of slinging blind recommendations...
What do you imagine you'd like to do? The categories are basically going to be:
Tank / Healer/ Support / DD. There are some hybrids, and some classes that can do multiple things. Instead of getting into all that, why don't you tell us what you'd like to do and how you want to play?
Then the peanut gallery of nerds (self inclusive) will shower you with recommendations
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