In principle, all four factions are open, [@BingTheWing].

Either approved or in the making, we've got nine Sith, nine prisoners, four rescuers and five strike teams. As the last two groups will (mostly) be working together, that means its all fairly balanced.

As such, you can make:
[list][*]a Sith apprentice
[*]a captive Jedi padawan/knight
[*]a Jedi Knight on the strike team
[*]a Jedi Knight or Padawan among the rescuers
[*]a republic soldier that is part of the Strike Team[/list]
Know that the last option (Republic Soldier) will mean that your character would be at a severe disadvantage in quite a lot of the situations that happen in the RP. He or she will be far more likely than the others to die.