If I had to guess I would say something like this,
lots of explosions and lasers with an economy based on mining splog the most valuable mineral in the universe. You could also have Forts that are solid so no need for battlements or anything silly like that you just blow them up.
Sea warfare could easily be adapted for space with even bigger explosions and lasers did I mention lasers, I think it would be epic. I could go on and on..........and lasers
Really looking forward to Galaxy Total War.