Few notes I took after watching the film a couple times.
00:35 Anticipate the cons flight path. Here we see two bishops chasing a friendly (knight) he pitches up and then turns right, towards you. The bishops are likely going to follow him which leads to tough front quarter shot on the P-47 which is under your nose. As soon as the friendly rolled and pulled down and towards you I probably would have just aborted my attack and pulled up to save some of the my alt, and reassessed the situation. If the 51 continued to extend you may have been able to make an attack on it with a higher percentage shot or before he has a chance to rebuilt a lot energy. Or at the very least the attack direction would have taken me away from the the rest of the cons in the area.
As is you did the next best thing which was you didn't surrender too much airspeed. If you pause the film immediately after your shot on the P-47 you'll see 1 friendly and 5 bishop/enemy in icon range.
01:30 I think this is where the sortie starts to unravel a bit. Under the circumstances you're not going to catch that P-51 before he gets to his friends, and you're chasing him directly towards his field. I think a better options would have been to let him go and maintain some speed and alt, when you're low and there are that many people around even with speed it's too easy to get your energy bled out and in trouble. As is you soon run into Ghi who is a very skilled player, such encounters usually end poorly.
02:00 Another high point here you begin a rope attempt which despite a couple hits get's you position on the LA7, Ghi is a very good shot so I would treat this as a positive rather than worry about getting plinked a couple times.
02:50 You don't press for a shot here, which is a good idea. The LA7 is breaking hard and is considerably slower than you are, if you continued to try and pull lead you would have played right into his hands. Instead you break off the attack and pull up which was the right move, the problem comes when you quickly roll and pull back down into him. You're still substantially faster than him and now heading downhill, conversely he is slow and pulling up. He get's behind your 3/9 line and get's more hits this time with damage. At this point with elevator damage that will limit your maneuvering and heading directly towards their base your options are somewhat limited. I would probably try to use the one thing I had going for me in this case which is you're still packing a good deal of speed and I would try to find a way to get to some friendlies which admittedly would be hard because you'd have to fly through more cons to get to them, but the other speed option is to head out to sea where the LA7 would eventually catch you after a long chase. As is you make a pretty hard turn and I can guess it's to avoid the two scenario's I just painted but as is that just bleeds speed and let's him catch you quicker.
To address your question about what to do with someone inside gun range and with a low closure rate, there are couple things you can try but at this point it's essentially desperation time. Obviously the best thing to do is keep them from getting there in the first place, but assuming we're past the point and assuming that you have some speed to work with there are two things that I try to do. One is I try to get out of sync with them, since they're going for guns you pretty much know what they are going to do and where they are going to point their nose. As I mentioned above about anticipating your opponents moves, anytime you know what they are going to do next you can try and exploit that. So I will roll and pull either right or left all the while watching them when I see that they are starting to roll to match my lift vector now it's time to go in a different direction, you want to keep them out of sync with you, at the same time I'm trying to create as much of a speed difference as I can in a very short period of time. Lots of rudder, aggressive throttle work, throw out the anchor. This may solve the immediate problem, keep them from getting a guns solution but you're not out of the woods, I also start screaming for help because basically all I'm doing with all this is buying time. Even if I get him off my dead six if the other guy knows what he's doing at all he's still in the drivers seat and I'm still in very deep trouble. One thing you would need to do in the above scenario is keep your eyes on the opponent. Looking back while flying and maneuvering is a little awkward at first but like most things get's easier with practice.
