always fly with tracers off in fighters as people dont seem to jink as much when theres nothing to avoid, I find it really helps me when gunning in a bomber as the attacking plane will get in too close.
Gvs: off if i'm attacking a town in an osty. but on for base defence as it makes the atackers more wary when attacking you.
Field guns, tracers off, I love picking off guys when they think the ack is down had quite a few double figure runs
I sometimes turn the tracers on in my fighter when its night time as it looks nice