My guess (fairly certain) is :Because the Coulomb is non-physical in electricity. Charges flow when a potential is applied to a system, but atoms (in solid state) rarely disassociate by themselves without an applied potential.

Many many more columbs exist without there being a net charge, or without a flow of that charge. Thus electricity being directly the flow of charge, the fundamental unit respects that flow.

But it could easily be defined as some multiple of the elementary charge (for example), just as the second is defined by properties of the caesium atom.  That to me makes a lot of sense.  Plus, it seems wrong to consider any rate as fundamental, since a rate is inherently something per something else.

The ampere is currently (until the proposed redefinition goes through) defined through an actual measurement of force, whereas the coulomb is defined and derived through the ampere and second.

pun intended

Yes, but I feel like that should be flipped.  Just as the "tick" of caeseum was measured in what we thought was a second, then we turned around and redefined the second based on it, that could be done with the coulomb and I feel like that's more logical.

The reason why this and other standards are the way are is because https://en.wikipedia.org/wiki/Operational_definition

It's the same exact relationship as watt to joule, I guess it's easier to just include time since you need it for most practical applications.

I don't quite follow...  I ask because to me, the case for coulomb being fundamental is obvious and intuitive, while I can't think of a good case for ampere, and while that could very easily just be a case of me being weird, I've yet to see any logical basis, or any officially stated basis at all for why ampere remains fundamental.  I assume there must be a good reason so I want to find out what it is.

That wikipedia article does state the reason, it's because ampere can be physically measured and realized while the coulomb is a theoretical unit derived from the realized ampere. How can the base unit be derived from something else? That doesn't make sense if other units are based off it, especially the one being derived from.

How do you measure the coulumb though? You rely on definitions of avagadros number, faraday's constant, and on experimental results of applied voltages for disassociation.

The cesium atom example is directly measurable. Which is the difference. 

Hmm, I think I see now.  Even if it's not defined by an actual sample sitting in a lab somewhere under a glass bell, it still has to be something you could theoretically measure.  Well, it still feels wrong to me and I don't think that will ever change but at least I have my reason now thanks

Are there any quantum units for measuring the flow of electricity (number of electrons, or rate of flow) past a specific point in spacetime?

Well, you could make them up as needed.  Elementary charges per planck time I suppose But good luck measuring anything on that scale.

I still feel like there should be something more to it.  For one I'm not convinced that the ampere is any more measurable than the coulomb.  They base it on the force generated between two parallel wires carrying current, from what I can tell.  That seems just as prone to error, and to involve other units as measuring the force between two charged plates, for example.  Additionally, I feel like the purpose of the base units is to describe the building blocks from which all other things are constructed, and as such, whether or not it's easy to measure is not the top priority.

I think that's a fair assessment, but at the same time, you basically never use coulombs by themselves. Most of the time you use coulomb's law, you are using elementary charge units for example.

Really I just think that Ampere is a much more useful unit. Coulomb's are a huge unit for ionic charge, but a tiny unit for molar charge. 

Anyways, effective March 2019, the elementary charge will be defined as a specific fraction of the coulomb. So soon your issue will be resolved heh.

That's a good point too.  tbh, I think that's got more "weight" to it than the measurement thing.  All the other units are "familiar" and useful in everyday life.  We don't define distance by the planck length or a mole to be one atom afterall.  And yeah, I had heard they were changing the definition somewhat.  Not quite what I had in mind but it is still an improvement imo