1). Just a question about the proposal: round up on AD, or down? For ships like the Drakh DDF, Narn T'Rakk, and Abbai Tiraca, it's an important question.
2). Another vote in favor of such a change, or even both (as combined with tschuma's idea -- although I would think you should be able to continue the Close Blast Doors order indefinitely)! I hated several special rules changes, and this was one of them. Its return on investment was a 33% increase in survivabilitiy, and, if you had one main gun and a few afterthought guns (like the Chronos!) it increased the value of your ship by appx 32% -- way too much. The others with changes I admit to despising are Launch Breaching Pods and Shuttles, All Stop and Pivot (I maintain I'm still right about these!), and Concentrate All Firepower (I admit to being wrong about this one).
EDIT: Da Boss,
Absolutely, it's an increase to the Drakh. A major upgrade, especially in that it would dramatically increase the chance of the Raiders getting to engage a target ship. Such a change may be too powerful in the case of the Carrier (which just wants to survive until the end of the fight, then emerge and kill off all the remaining Skirmish ships). The Nightmare of layered defenses that you list for the Drakh Light Raider may be bad, but keep in mind its offensive output would be expected to be 1.505 damage and crew, total. For a Skirmish ship, that's a crime. If you fire at a CBDed Light Raider with a heavy weapon, you're either massively outsinked (possible!), or need to seriously reconsider your targetting priorities.
Such a rule with CBD might even make the Drakh Escort Cruiser viable. Well, OK, yeah, it wouldn't -- it's an atrocious ship -- but it would make it less horrible (I would have loved it to have a couple more pulse dice around and substantial Escort and Antifighter capability like 5; then, I'd take it!).