Has anyone figured how how MGP worked out the ships yet?
I once quizzed August on this very thing.. apparently there is no standard rules by which vessels are constructed they are simply built on a case-by-case basis.
I have even tried collating all vessel info trying to find some common denominators by which to determine a system and in all honesty I couldnt find one. I suspect any coherent system, made to build ships for Bab 5 would be a prelude to a heap of revamps and re-writes concerning ships released so far in order to make them usable by whatever system was made.
At this point your probably thinking.."um well thats no good", but in all honesty just making a vessel to suit your needs at the time and statistically giving it what bonuses, modifiers and features you need really does work as good as any system.
There was a system done for modifying vessels, allowing you to customise various aspects of them but that was in the Babylon 5 Companion that has yet to see release.