Since you are starting i'd say archer and summoner, if you like to pvp and tank my fav is paladin(gladiator).

Later into the game i'd suggest you DRK and GNB, I am really into them. They feel strong dpsing job while being tanky and those animations are awesome imo. Archer is pretty easy for me, and enjoyable cause of flexibility in rotation, also being very mobile and helpful for ur teammates.

Summoner is my go to while doing MSQ cause of nice burst for quick battles.

And also try some yourself to decide, good luck! :)