hmmm...
Oddly Mongoose B5 RPG and ACtA do not match fleet lists or fluff from what I have seen.
We have more than a few rules in the game based exactly on 'we see it in this one episode' or less.
Fleet composition that we see in the show is not what folks seem to think is obvious. Primus operating alone, G'Quon operate in squadrons with no support, Demos/Vorchan operate in large numbers alone, Drazi hulls operate in squadronsof the same type. The idea of modern naval task forces with layered defense and special purpose ships does not have a lot of support from the show.
And common sense is the birth of all arguements.
I would work from the show first. This is the base we can all agree actually happened. ACtA/B5Wars fluff next (in that order). Only then do you go outside and try for the RPG (again, this is not consistent with ACtA) and/or other sources.
On the example of the carrier of course needs escorts. This is a mistake in applying naval analogies to a hyper space world. In a B5 world carriers can simply hyper away if threatened. Second is the role of escorts, B5 escorts can not shoot down that missle for you, or detect something that your main ship can not see.
If you begin forcing people to take 'escorts', perhaps a guardhawk for the drazi, you will simply remove carriers from play. Coming from an SFB background I can tell you that with certainty. You will quickly get 'carrier races' and non-carrier races.
Ripple