<sniff> I'm still waiting on the Kitty Hawk and all it's fighters and shuttles you have shown. I even added it to my personal shiplist (CVC Combat Carrier), and wrote up a "historic" profile...
At any rate, as to the Battle Tug...
(R2.10) BATTLE POD (P-BP): As tugs cost as much as cruisers to build, competition between the fighting and logistical elements of the fleet for construction funds is fierce. To partially offset this, battle pods were constructed and held in storage at starbases. A tug carrying a battle pod (the comination being called a "battle tug" and listed separately on the MSC) is operationally similar to a DN or CA. Thus, an expensive peacetime transport can be converted in hours to a serviceable warship. The battle pod weighs twice as much as other pods and counts as "two pods" for purposes of movement cost and turn mode.
Some battle pods were improved to the BP+ configuration by converting their APR to warp reactors (as well as adding a drone rack and two ph-3s), which allowed them to fire their photon torpedoes while separated from the tug and allowed the battle tug a higher speed in combat.
*****
Well, I don't know if any of that helps, as you're actually making a CV pod (which looks fantastic, btw)...