Turn speed is everything, as it allows both: dodging and alternating between the two thus increases your firerate, but I also found an AI exploit:
and this is even worse, we were just ramming the wall (standing still):
Edit: Oh, I see you're aware of it already and planning for fix it.
Then there's another observation - even when AI ship had better range, he still was to cowardly to shoot when I kept distance, as the result I was simply alternating between two cannons (I always chose turning speed upgrade when available) and I often won the enemy without him EVEN SHOOTING ONCE, even though he could. May be the targeting algorithm isn't certain at long distances?