A hall effect sensor measures the strength of a magnetic field as it gets closer or further away. There is no turning of a potentiometer, no gearing, and no having to worry about wear. It is the most accurate way to measure in the case of pedals.
As for a load cell, that measures the pounds (or kilograms) of force applied, much like a real vehicle. Instead of having to guess how far your pedal is depressed, you can use muscle memory to tell how much you are breaking. Overall feel is better than just using a standard spring and potentiometer brake pedal. I can guarantee you will be able to brake smoother, later, and more consistent than with your current set of pedals that do not use one.
I am working on a new simple to make for a DIY'er pedal design incorporating a load cell brake. This time I will actually complete it and do a full materials and tools list along with prices. The whole approach is to be able to do it with standard power tools and easily obtainable materials.