Cremator,
I think you have the right attitude in that you already want to focus on and practice your gunnery. If you see me in game, shoot me a PM. I'll be happy to show you some basics and some practice techniques.
Unless you are just an absolute natural, gunnery is one of the hardest things to learn and the easiest skill to get rusty at, if you don't practice. Also, every aircraft has it's own nuances to how it shoots, different armament, different ballistics, different effects of your convergence settings, etc. So, it takes some time to learn to use each aircraft effectively.
RotBaron is right about their being different "levels" (I call them "plateaus") of gunnery. Last night I was frustrated that I was only landing 2 or 3 kills in a sortie (and 2 or 3 assists), instead of the 4 to 6 kills that I thought I should have. I like to average 3 or 4 kills per assist, which tells me I'm hitting my targets hard when I set up shots. That's one of the fun things in the game, as you improve you can raise the bar higher and higher for yourself -- I guess that's the nature of competitive people, too.
There is also a lot of "good flying" that goes hand in hand with "good gunnery". I see lots of people who fly to get "bad shots" instead of flying to set up "good shots". That is something better shown, than explained though.
At any rate, I'd be happy to give you some tips at some point if you see me in game [ID: RynoRush]. Or just shoot me a PM here on the forum, and maybe we can schedule a time in the TA.
Keep practicing. And be patient (that goes for practice and when shooting!) - and the kills will come.
<S>
Ryno