Yes, they added a lot of content, since then. You can, now, flip planets like in Pirates of the Burning Sea. That means you can change who is in charge. And, when then you can build up a strong defense or crush it with a powerful invasion force.
All the graphics have been upgraded several times. Also, if you feel you need to make your own upgrades to the game. There is always modsource! http://forum.modsource.org/