The warp engines are definately bigger than the DN's Bernard.  If you go by the orignal mini.  Which is of course the basis for this interesting design....
I believe the Doomsday rules changed the thinking of the CVA to more of a DN conversion.  While it makes for another ship design it defeats the traditional thought of designing a carrier from the keel up.  The are so many limitations imposed by trying to put a flattop on a hull designed for other purposes.  I realize that's old navy thinking but since we don't have a space navy old school is the way to go about things.
Here is a shot of Atrahasis' design from a while ago. 
