If we considered an action that affected millions of people (a government leader) then this system would almost certainly fail to produce any actions in which everyone in the system (e.g. a country's population) wants a given action to occur.

Remember that this is assuming that the two actors in the system are of equal levels of power.

In society, this is never true. Where it is true, a thing does not become moral or immoral for quite some time. See topics such as abortion, which for some time were quite heavily debated, and only now, as the free-choice groups gain more power, is it becoming more of a moral action.

Therefore this system would not produce any moral actions and is functionally useless to that aim, which is something you agree with when you say:

if society had actors on two sides, of equal levels of power, with no ability to resolve those view differences, then no action would be produced. Society is so large, and so complex, that this situation rarely remains true for quite some time.

And, of course, this is not a pure matter of power, a group with a lot of guns is not going to exist forever, and if their actions have negative effects on society in the long run, while the society they rule over will consider their actions moral, all societies that result from that one will look back on them as immoral.

As well, social power is a thing, and morality is often based on opinion more than it is on other topics.

It all matters how you define the scope, how you look at the actions, and so on. There is no simple, concrete, answer.

Which leads me to think that you're essentially saying: Any action that everyone wants to happen is moral.

Only if you are considering the scope of only that person.

so the former is better than the latter according to Total Utilitarianism. This clearly is counterintuitive and not worth our time.

That isn't counterintuitive at all. It's actually something quite a lot of people think is the better option, with fewer people living better lives.

"Average Utilitarianism" states that having the higher average utility is favorable (take the above example and just flip which one is favorable). The issue with this is that this justifies enslaving a small population for the increase in average happiness for the masses.

Which has been done, and was considered moral, in the past. We even do it today, killing pigs and cows for meat so that humans may have more things, along with destroying forests and so on for the same reason.

add some rules to actions that have to be held for them to be considered moral

In my opinion that is evidence for the idea that, the theory of utilitarianism is too weak, it requires exceptions in order to function.