Free-Roaming Ships in Sins?

I'm not quite sure what restricts ships from leaving gravity wells but had thought it interesting the other day what gameplay might be like if it was a bit more.. open. If ships could actually go out into deep space and build. To go into it even further, have resource asteroids spawn randomly in deep space as well. Players would then build defenses around the asteroids to protect them. This thought really breaks the gameplay of sins as it sits but if done correctly i think it might be fun.

In case of what I just said wasn't clear, I'd like to try and make sins more like other rts' in that players could go wherever they want, any distance away from both planets and stars.

Anyone have thoughts?