I have used a bunch of carburetors on my car and none of them have been perfect. I am always changing this or that to try to improve them. the Edlebrock (or Carter) type stalls when you corner too hard. The Holley's stall the engine when you brake really hard. I am currently running a Holley Avenger 670 and after a year of tuning with a wide band A/F gauge I am getting pretty close with it. I have changed jets, squirter, cam, springs and needle assemblies to keep the mixture between 12.5 to 17 to 1 in each phase of operation.
EFI is the reason that modern car engines go for 200,000 miles without a rebuild. Carburetors never mix the fuel with the air perfectly so you always get some raw fuel washing the
oil off the cylinder walls and that causes more wear. Most carbed engines will have to be rebuilt before the 100,000 mark come up. That is the primary reason that I am seriously thinking about spending $2,000 bucks on EFI. The Projection 3 system is nice because the ECU is built into the throttle body. Holley, FAST, MSD, Edlebrock and Accel make "self learning" EFI systems that should be easy to program. However, as you have seen, there are so many components that can fail. EFI systems need a steady voltage supply. You need a 100 amp alternator and a voltage stabilization device like the MSD capacitor. That may have something to do with your problem. They also will not work correctly if you have a camshaft that's too radical. Too much cam overlap drives the sensor crazy.
Since I run long distance rallies in my car, I will probably stick with the carb. I have fixed it on the side of the road many times. Try that with EFI.
However, there are companies that reprogram the stock Ford or GM ECU's so you can run with EFI systems tested for millions of miles. That may be the most reliable way to do it and that is the direction I will continue to investigate. Good luck with yours.