turning ks on would be horrible imho.
In the past few flights I've had, I've seen a few noobs shooting bullets down the runway, boy was I glad ks was on. If it was on, I invision what the old DA was like. You vulched me, so now I'm gonna vulch you. Then each parties bring their buds, and now you have a fight over your base between your team and probably the enemy. I can only imagine this would put the community in a meat grinder and only serve the purpose to ruin the experience of AH.
The other aspect, is that turning ks, removes any responsibility to you. If you have poor SA, and just spraying, what does it matter who gets in the way? Maybe you are chasing a con, another guy wants the kill, so he just blasts you first. Also, shooting a guy because he is shooting at a con, that you feel entitled to, is just as bad.
I think If you have a group of people that are 100% dedicated to flying in a fashion that might resemble a more realistic scenario, then ks off would be fine. but this is the MA, and it would only take 1 person to degenerate gameplay.
My advice, keep playing for fun. If someone shoots the enemy down before you can, next time do it quicker. The minute you stop worrying about who is killed who, how many kills you can land, and what your score is, the easier it is to let these trivial things go.