Ok...
When there is three enemys at all costs keep the energy advantage over them, you have no problem disengaging if it doesnt work out. You are way to eager for the kill.
Stay up high, see which of the 3 is trying to climb up and get slow. That is the newbie, you kill this one first.
Dive later and only when you are close to the enemy. Stay high over them a bit to make them nervous till one of them gets bored and climbs up or forgets you and doesnt see you anymore.
Stay above/behind, change the targets... untill one of them looses sight of you....
Be sure to pick up enough speed... sounds to me you drop the dt and start diving straight for the enemy. Release the dt earlier and gain some speed/more alt.
Dont go straight up after the shot. After doing anything you can to be sure he wont get a shot after you pass him, pull up in a less steep climb till your speed is down to 200mph and then lvl and pull around in a gentle circle.. I am no expert on dora but it seems to me you burn to much energy on your vertical pull up.
Try to come down from straight above your pray. Gives him less chances to dodge.
Dont slow down and latch on anyones six if there is more than one con. You have to get the boom n zoom down with that plane, you cant win a slow turnfight against multiple enemys.
There is no need to latch on any 6es since you can just shoot them in the zoom.
Dont point your gun straight at the enemy. If he goes in a gentle right turn, aim generously to hist LEFT. Once you come closer he rolles and breaks hard left, you get a nice profile shot. He continues to tighten right, just zoom back up.
Stay fast.... nothing wrong with a fast turnfight, the great roll rate makes the 190 good there, also nice big rolling scissors maybe... but when he slows it down try to nail him and then break away.
Of course you can turn fight, let em overshoot, scissor, stall.... but why loose your advantage if you have it?
Keep your speed, cherry pick those that cant dodge you, run home and laugh at the frustrated chicken/ runner comments.