Ya at the moment the SSA is the major power in the galaxy.
The Legion is a few small groups like ours sent on different missions. Jason and Danny are the leaders and choose which missions to take and who to send where. So we might run into another group some time, but it isn't a huge organization like the Blue Suns or any of those groups. 
And that is probably a good idea I'll get to changing that when I decide to get out of bed and go to my computer.