Unfortunately there is very little or nothing you can do as a cyclist to prevent motorists from overtaking you in dangerous places. A lot of otherwise rational people develop a dangerous and aggressive mindset as soon as they get behind the wheel and all you can do is ride carefully, as you seem to do, and prepare for the MGIFs.
A good part of my commute is on narrow country lanes and I am frequently overtaken by drivers in dangerous places, at dangerous speeds. There is no way I can prevent them doing this other than riding primary, and doing this puts me at risk from traffic coming from behind at high speed and oncoming traffic. It does however, give me a safety cushion of 2 - 3 feet from the verge so I will usually adopt this as a survival strategy.
To give an idea of this the picture below shows a stretch of lane I ride on quite often. It's winding, with a few blind crests and bridges like the one in the picture. The speed limit on here is 60mph, and a lot of drivers will do this speed. Don't be fooled by the hatchings on the road in the foreground incidentally; it's a weak bridge and the makings are there to keep traffic in the centre of the road, not to denote a cycle lane.
I will never wave a driver past when the road is clear - if they do go past and I misjudge it and they hit me or another road user where does liability end up? On the (all too rare) occasions when a driver passes wide and safely I'll give them a wave of thanks but that's the sole interaction.
Finally, I carry a camera
in plain view. It works for me in two ways.
Firstly, and most importantly, the sight of a camera does have an effect on how motorists behave around you. I find I get far fewer close passes and motorists are less likely to pull out in front of me when I'm carrying the camera.
Secondly, because my local police force are quite pro-active, I can submit video to them easily and they will take action. Their normal process is either a warning letter to the RK or a visit to the RK's home by traffic officer, but they can and do prosecute using submitted video - the screengrab from the video below earned the driver a visit from A&S Police. The warnings do work; I see the same vehicles frequently on my commutes and have never seen a repeat of a reported close pass.
