the problem is that NPC battleships (and other caps) dont differ much in level than NPC fighters. A mission randomly generates npc's based on their level related to mission difficulty.
So, for a 300k mission, you might go up against a dozen or so fighters, or you might go up against 4-5 battleships =/
What I find laughable is how much damage and hull the NPC battleships on missions have - they take forever to kill and can rip you apart pretty easily if you dont pay attention - however, NPC battleships that arent linked to missions (like those flying over manhattan) can easily be solo'd by anyone with a bomber or cap because they do pathetic damage.