As for which techniques are going to be most effective, it's going to be the techniques that you have practiced the most. Muscle memory is developed after doing movements thousands and thousands of times. So at the time that you are in a battle everything should be second nature and nothing should seem complex.
Actually you can see how muscle memory works in sports. If you play basketball all the time you don't have to think about the rules. No matter how intense the game is or how much adrenaline you have going on both sides you can't just pick up the ball and start running. You have to obey the rules of the game at all times just as you have to obey the rules of your art at all times. Is Kobe Bryant thinking about dribbling while he is playing? Or is he thinking about the open opportunity. Most people don't practice as much as Kobe at basketball and may have to think about things such as passing, dribbling and shooting. A movement like passing behind the back would seem foolish for someone who has not mastered the basic passing. This is also the case with martial arts. Just remember how many thousands of years have been spent to perfect the martial arts . There is nothing that is designed to be "flashy". It is only arrogance to believe that in your short life span you can develop something better than what has already been refined for generations. This includes Bruce Lee who even though is the greatest hero of martial arts. Even after he developed his own style, he could never beat his master.
My advice is to make sure that you can do all of your techniques in real time. Have your friend start punching at you slow while you perform the counter. Do it over and over, faster and faster. Do it everyday with the same technique for a month, a year, a decade. I promise you that movement will be effective no matter how complex it may seem.
In the end I hope that all of you can understand when it is time to fight. When someone disrespects you? Betrays you? Steals your girl? Takes your money?
Of course it is up to ones own discretion to decide whether or not this is the time. When I was younger I used to fight a lot more over many different situations. As I grew wiser I was able to realize the unfairness of the situation. Even though this guy is bigger than me, stronger than me or even has friends with him, it is still unfair. I spend all of my time understanding the weak points in the body. Thousands of techniques a day trying to develop the most power and speed that is possible. Maybe this guy did call me a nigger. Maybe I do have the right to respond with force. But in the end he is only trying to fight with me because he is ignorant. No matter how angry or crazy someone is, they cannot overpower the physics of martial science. You should consider your art the same as carrying around a gun. Would you pull out your gun for any argument that you had at a bar? The techniques that you may be fiddling around with are the same ones that were used in the battle fields of China to kill thousands of soldiers. Make sure you weigh out your options.