Everything you described is basically what the agent is. If you like that style, just play one of those. Games like swtor can't afford to have tons of classes -- with awesome voice acting and thousands of hours of it, they can only have a few storylines and I think they covered the playstyle spectrum pretty well.
I think your right with that one. But it would be cool for 2 more classes one on each side. Maybe not this one but something new and way different gameplay then the classes we have now.