I've just lost a game and I analyzed the record. Among other mistakes which I've made there was small thing that contributed: I had one choke point that I defended with Illums and Hangers, and my opponent attacked with Illums and Carriers.

The forces at first were roughly equal, i.e similar number of fighter squadrons and Illums. However that was a very long and hard battle and I've noticed one small thing when analyzing the record: Hangers don't produce fighters as fast as the carriers. It seems that eventhough they have 3 squadrons, they can still only manufacture fighters only for one squadron at a time.

So the hangers are sitting there with 3 empty or almost empty squadrons and tons of anti-matter, but they're hardly manufacture fighters. The carriers on the other hand manufacture tons of them. The end result was that after a prolonged fight my opponent was still fielding a large number of fighters while mine were all dead.

The moral of the story is: don't rely on Hangers, use Carriers instead.