Oh, a german Aircraft Carrier- equipped with two fighters, of course- can change the tide in A&A:Europe quite significantly. In combination with destroyers, you can easily guard the Convoy Routes, intercepting those bold attempts on liberating them with one ship (which occurs quite often with my fellow players), freeing your submarines to raid, pillage, plunder and otherwise pilfer their weasely black (or grey) guts out at the US’s East Coast. “I love the smell of burning fresh- built ships in the morning”, me says ;)
If you can afford a Battleship, use it as the “boogie man”- somehow most players fear to attack a Battleship because of its 2 hit points. Let it roam the seas with your carrier (and bring a destroyer against these pesky subs) and voilá! It’s a far too great threat for shipping lanes to go unchallenged, and challenging it costs IPCs your opponents desperately need to stem your flow of Panther tanks rumbling for Moscow.
Besides, AC simply rock model- wise.