Sins isnt a completly new idea, there was a game by ubisoft called "conquest frontier wars" with the same idea. In this game you have planets connected with wormholes. It was a little bit more like C&C styhle, but in space. There also were some very nice Racesetups ...
You also have Capitalships with special Weapons. The Terran Battleship also has a shieldfeature similar to that from the kol battleship 
Iam pretty sure that Ironclad knows the game before 
Carrieres are in the game too
3 races: Insects, Humans and energylifeforms
But this game just havnt the lobby which sins have.... So the publisher has forgotten this title 
hers a video. It isnt a very good one, but maybe it gives an idea
http://www.youtube.com/watch?v=FvAEE6k6doI
greets
