Ho sorry I missed one paragraph in your question 
Well anything related to the number of entries won’t work as it won’t be differentiable.
You can renormalize each value to get their number because that would give you a gradient of 0.
I guess you could try to center the parameter and use the standard deviation? You measure how much each tensor varies from a mean. In theory, you could represent them as a mean value and their offsets. So the closer they are, the better?