Could you have a problem with your proportioning valve? A semi-plugged or restrictive proportioning valve could produce similar symptoms.

Didn't know it, but I had absolutely zero rear brakes for around five years on a CJ Jeep I owned, due to a missing spacer/gasket in the proportioning valve. Wondered why my rear brakes never seemed to wear any.

During those years the Front brakes seemed to do the job, as 70% of braking is in the front, but was such a surprise when I discovered the fault.