If you are looking to go Ranged, I'd go with the Trooper: Commando or Bounty Hunter: Mercenary. Those are the more damage oriented Advanced Classes, but they still wear heavy armor.
For Melee, Go Jedi Knight: Sentinal, or Sith Warrior: Marauder. The dual wielding, lots of damage, Advanced Classes for those classes. They only wear medium armor, but are still pretty tough, and dish out tons of damage.