Very nice so far. I would imagine most of the detail on the back of the model (engines, reactor, etc.) will be added by texture as "armour plating" or something of the sort. The engines are of the right shape, so the engine trails can be put inside nicely and it would look good and "realistic" ingame.
By the way how many turret hardpoints can you fit on this model? Since ideally this would be a medium battleship, the amount of turret hardpoints should be about 12 to 14 depending on how well they can be fit on the model. Taking that into account, if you want you can actually model in mounts for hardpoints or something (but its not a requirement, just an idea).
In addition to that I see you have modelled in a hangar like one in one of the vanilla battleships. Very nice, we'd be able to animate it in the future and it would work completely like a vanilla bs.
