I rarely gun but know what I want my gunner to be doing/looking for.
Probably the right answer here is that it depends on the pilots play style and set-up.
I tend to be aggressive when ABC is all red and I like flying in close - cause I want the gunner to clear some soft targets so our ground can get a foothold again. When there is a strong base on abc and it's all blue I then play more defensive and stay back to protect the caps from incoming threats. I have an unspoken non-aggression pact with enemy air and normally only fight them when they come to me, or I see a sneaky opportunity for tv/tow. But I hate gunners who attract non-aggressive air players with 30mm who then turn aggressive. The focus is on the ground and only engaging with air if needed / good opportunity. Minimal attention is good.
Many gunners tunnel vision on what the pilot is attacking, at times you gotta split the fire and OO around to find potential threats (soft targets with launchers/stingers). Remember the pilot has x 2 tows both can do 35 and u can get near 60 dmg with 1 pod of Zunis if well placed and all hit - the pilot has enough ammo and suitable weapons to kill a piece of armor themself. So decide if you think 'he's got this' and if the area is hot go OO around with the 30mm, if all is clear combine on what the pilot is attacking. Use the whole range of view, check far right, far left and below when potential infan threats are close. Some very good infan players on RC1 who are badass with launchers vs close air, don't under-estimate those guys (it's way easier to hit a target broadside than head-on).
The initial attack on armor target should be TV/TOW first as if you shoot cannon/rockets first on unaware target you ruin the element of surprise and they will become aware of your position and start trying to escape / slinging shells your way and spotting you. TV and tow together will do high damage and possible mobility hit which means it can't escape while you finish the kill. You want to be as quick and efficient as possible with each attack run and do as much useful damage as possible before you are forced to break.
Remember the pilot can see everything straight ahead, you need to be pro actively checking/searching about for what is outside the pilots view. Any soft target threat to the AH flanks is your responsibility. Toggle back to TV view frequently to see if pilot is in seek or pursue mode, if he is pointing at a target then TV (also use audio cues... if you hear the pilot fire a tow switch to TV view and see what he attacks and send a TV along with it). After go back to 30 and check around flanks / below again.
Hold the 30mm fire until you are stable (when the pilot starts using weapons or in a smooth maneuver) just try and be reserved with ammo and know what to prioritize in any given situation. Know in what situations you need to maintain a low profile, the last thing you need is additional attention.
Top priority to help the team is any enemy cappers need to die - including infantry and the 30mm with therms is perfect for infan killing.
The 30mm is an infantry / light armored killing weapon the TV is a heavy armor/air weapon. 30mm should only really be used on heavy armor when in a 'do or die / pilot has low ammo'' situation or when there are no soft targets to attack - but since it does small damage to heavy armor you may wanna reserve it. It's also very effective at killing buggys and damaging enemy air at close range (again light armor), but when the range is too great, you should just save the ammo and attention
One player called Traveler uses zooms and he is an excellent gunner so outweigh the pros and cons of both to your mind and decide which one makes you more effective (in terms of helping the team overall).
Having a good aim/control is obviously advantageous but not necessarily helpful to your team - if you apply it to poorly selected targets/areas. A good team player brain is what helps your team and vehicle buddy.
Push it to the limit and always keep up the pressure, doesn't matter about KD or how long you survive for.
Anyway, that's my thinking on it.
@BEATYASILLY - You should ask this guy lol.