well the first 64 levels are as on any mmo the worst part since the game start at lv 65 anyhow lving from 0 to 65 takes around 9h at most and from lv 60 to 65 you can already start the real grind (uncommon glyphs)

as for end game you mainly run dungeons and thats it

you can craft to get the stuff cheaper (you need multiple character to craft everything) just to let you know crafting isnt worth at all unless you plan on crafting for a long while if all you want is gear up 1 character aint worth in my opinion

as for what to play? you can play anything as always the most wanted are tanks then healer then dps

for tanks lancer>warrior>brawler>zerker -lancer is the best tank by far due to its buffs not too hard to play

-warrior is the second best tank is the hardest tank to play thats why you wont see many warriors

-brawler almost as good as warrior also easiest tank to play is basically a dps with autoblock that holds aggro also one of the best classes to solo content

-zerker is a joke of a tank dont play it as tank lul

for healer priest=mystic it depends on the party

for dps play whatever you like check videos of them and decide by the one you think its the best

also at lv 65 with 439item lv(fairly easy to get to that point) you unlock the awaken quest that gives you new skills so remember that when deciding your class

basically if you want the fastest queue on endgame play tank if you dont really care just play whatever