I don't find head-ons hard to avoid unless I'm very slow, and if I'm very slow with the enemy being able to point his guns at me, I deserve to get hit.
In the cases where I have decent speed, I just fly off angle to the attacker, then pull g's in a different direction back toward him (still off angle, but a different off angle) as he comes into the about the 800-yard range. It is rare that I take any hits, and when I do, they are usually not major hits.