For class, i always preferred a ranged class, with wich i had a better overview of my hero team and the battle.The easiest most powerfull classes were; Ritualist with an offensive Spirit build, and Necromancer with a minion build. As mentioned, a good team of Heroes is more important.My Hero team ended up being so good that most of the time i wasnt even needed. If u like i can try help u in game. Send me PM here, or contact me in GW2.I live in Europe though, so maybe timezone difference issue.