I think the game could use a new class. In all honesty it probably 'needs' one. And I really like the "defecting" idea.
My idea would be a defecting knight of Zakuul.
This could be a class that allows you to start at level 60, like with the Level 60 token. A fast introduction to the class abilities through a groundlaying story arc.
The choices you make during this introduction would determine your imperial or republican allegiance.
This class would not need the level 1-60 story and companions. Which is no longer needed that the game has stepped away from the class stories.
It could also add new weapons like shields and lance/polearm.
I don't know, but I really like the knights of zakuul and would like to play as one at some point.