you never have the correct change

As a result change accumulates. Every so often I bring it to my credit union and throw it into a machine and deposit it for free.

oftentimes you get changed short

It's very rare and the mistakes sometimes happen in my favor.

takes up too much space

Not usually. Only when on occasion I need to process a lot of change at once is there a significant space requirement.

you have to balance between not carrying too little and not carrying too much

This is trivial. I never spend more than half a second on such a decision. Usually I know instantly what to bring.

hard to track spending

That's a feature.

i believe that we need the option to use cache in society

I believe cache must remain legal tender and refusing to accept cache should result in a felony conviction plus one year imprisonment.

That said, I would eliminate the penny and the nickel, and put the quarter on a serious diet. Then outlaw all the .99 and .95 type pricing. It might be OK to do away with the dime as well and only leave the largest coin in use.

Privacy and the freedom from oversight by any large entity are non-negotiable.

The only oversight I support is me doing oversight on you, and never someone else doing oversight on me. I am not a masochist.