Well, it depends on what aspect you look at. Each class has its specialized weapons to suit it's combat forms.
But if I had to pick one, I'd say the rangers. Making the lives of creatures miserable from a safe distance
Hence my biggest achievement on PSO being my level 143 RAcaseal named Demi, shes a walking machine-gun toting tank
Once I was Valis Warrior, and then the Redeemer. But now, I am back, with 7 years experience to my belt here.