Ok i tried it. So yeah, as you said, it is pretty much unbalanced for now. The Codex mod (
http://fractalsoftworks.com/forum/index.php?topic=2749.0) rated the BFG ships more than 10 while the vanilla are around 1. So i tried some stuffs with the current ships with trylobot ship editor. I basically changed the weapons mounts according to the BFG rulebook (on GW site) and got this.
Much less mounts on the Hulk but still enough Dakka to wreck most capitals ships. I put 6 360° turrets, 2 360° dorsal lances and the rest are batteries and torpedoes tubes. I think this change is more important on the Space Hulk as your version got so much mounts that it make nearly impossible to customize the weapons (even though mine got an awful lot too)
Not much changing here. 1 bombardment canon, 3 360° turrets and the rest are batteries.
As the class Apocalypse isn't equipped with batteries, it get 9 lances mounts and 4 turrets (and the nova cannon of course). This really show the mindset of the imperial navy. Their ships are quite specialized and pretty much defenseless alone. Each ships tend to be boating specialized weapons and counting on the rest of the fleet to do the rest of the job. So yeah, the apocalypse is actually a massive laser boat.
I didnt change much here, just removed the front lance as the Gothic isn't supposed to have one. And reduced the torpedoes tubes to 3. As they were just so damn overpowered. Speaking of torpedoes, i am pretty sure that BFG torpedoes would act much more like Starsector Pilums launcher as they are somewhat guided weapons.
For the music, i am not sure you should put DoW music in this mod. Not that they don't fit in. But due to copyright stuff and all, you risk some problems (even more when you know how zealous GW lawyers are). Also, the music folder by itself weight 64 Mo which is damn pretty fat for a 0.1 version.
Edit: After re-reading my post, it sound so damn rough. Sorry Pelhamds if you feel offended by it, it was not the purpose. I am just trying to give some advice without sounding like a douche. I'll try to show some "builds" for the other ships when i'll got the time.