Refer back to my post on your thread about your films a few threads down.
There are 4 main modes to fighters in AH.
1. The MA
2. Special events
3. 1v1
4. Monday night madness/KOTH - type of small skirmish
Understanding how to be successful in each of these modes takes a lot of time and practice. Some people are very successful in one mode vs the other. Some really great 1v1 sticks aren't that great in the MA and certainly moreso vice versa. Being skilled in special events like Combat Challenge, FSO, and Scenarios take a different type of skill and understanding than flying in the MA or small skirmish fights. Being great in 1v1 air combat is very important for all 4 modes, however not necessarily the most important in the MA or scenarios, or even small skirmishes.
First and foremost, it's all about knowing your plane and what you can get away with.
Every plane has a strength and weakness. Some planes weaknesses are much worse than other planes weaknesses. Understanding plane selection will help you be more successful in each mode. A general rule of thumb for the MA is, you take a turn n burn or decent turning low alt plane for base defense (spit, ki84, 109, La7, Nik, Brew, FM2), and a higher alt E type plane for attacking bases, (P51, P47, p38, 190, C205, 109k/g14, F4U, tiff/temp) If you look at generalities, most foreign planes are defense planes and most allied planes are attack planes. You don't have to to stick to this, I'm just pointing out that they were designed for those specific abilities to allow them to be more successful in their situation.
Secondly, it's about understanding the fight.
In 1v1, You are both flying the same plane with no outside problems; this helps you learn the planes envelope and other evasive 1v1 tactics that can be utilized in other modes to gain sucess. In scenarios, you are bound to specific plane sets which means all planes have a relative performance standard and there is an objective to follow. Strenghts and weakness of the planes can be measured easier. In the MA, you could either be fighting a latewar plane set horde with bombers trying to take a field or fighting a furball vs fighters off a CV or in-between bases. Generally its easier to shoot down bombers and get a few kills than it is to get kills and stay alive in the furball. This is where you can improve K/D hit % and points. Going for the bombers over the fighters can help your success a lot. Planes of all different types and years with no actual objective and who knows what their motives are and how many people are helping you is what makes the MA very challenging, especially when you chose to fly a plane with a greater weakness in a given situation.
Thirdly, understanding what is fun to you vs what you label as successful. This is the hardest concept I believe because it involves emotion. Are you disciplined enough to be your idea of successful over your desire to want to have fun. Example- do you chase a guy to the deck you are trying to shoot, or do you pull off once too deep understanding that other cons may be attempting to engage you if you get too low. It's very fun to chase them, get tangled up in a 1v1, and try to kill them, verse not chasing and pulling off to avoid other planes diving on you. Your fun = I should 1v1 this guy no matter who is around, but your idea of successfulness = I should pull off and regain my superior alt advantage over the rest of the field. Your fun = I can try to outrun the spit in my 190 vs flying straight and extending away knowing you probably won't be able to out turn them. It's boring to run, but it's successful. What do you choose? This type of decision can be the difference between landing kills or getting tangled up and ganged in the fight. Knowing when to be aggressive vs when to pull off is such an important concept to aircombat in the MA and Scenarios. In small skirmishes you are constantly in a fight and not worried about K/D, but in the MA if you want to land more kills, you have to be patient and know when to pull off and how to escape the fight/horde coming at you before you get ganged. It's obviously easier to escape the fight in a late war attack E plane, which is why so many people fly them to avoid their SA failures and easily "extend" away. That's why I give 190D and most P51 pilots a hard time as running away is the easiest form of Aircombat albeit you do have to be patient and disciplined not to turn with planes you can't beat 1v1. This is why many 1V1 masters dont have the best fighter stats in the MA. Many great 1v1 fighters don't have the best SA, they get tangled up in 1v1s and often ganged, many also fly far inferior planes that make it challenging to escape the fight without other friendlies around. Fun vs Successful and the in-between is what you make it.
Lastly, cause this is getting long, my favorite. Learning defense tactics.
So many of my kills come from the overshoot. You will always have planes diving on you and learning how to counter them not only saves you, but gives you a chance to get some shots off and hurt them or take them down. This is a key concept in all 4 modes. Reversing planes can keep you alive so much longer. You can drag a plane out to a 1v1, reverse them, gain the advantage and get the kill. It opens the door for a lot more kills. If you are able to get defensive kills it helps your K/D and K/S a lot. It helps you stay alive in the skirmish. It helps you stay alive in the scenario when a guy is chasing you and you have no choice but to turn. It all comes down to SA and execution of the overshoot.
If you want to have a good K/D in the MA and scenarios. Focus on getting 3/4 kills a sortie and landing about half of them. In skirmishes and 1v1, focus on defense and pushing the plane to full envelope and eventually your skills will come together to be "successful" in all 4 modes while still having fun.