"1) The US is NOT the only one slurping, snooping and pooping. Just the one that's been outed in the public press."
Outside of the "5 eyes" the amount of "slurping, snooping and pooping" by the rest of the world is minuscule in comparison.
"2) The EFF expects that an angry letter or a resolution will do something or cause something to change? I don't recall any pronouncement from the UN stopping any wars, border fighting, etc. or any country saying "oh, your right, we need to repect our citizens"."
It is the actions of the member countries that dictates the UN's response to any event. Decision making in the UN Security Council (the only body in the UN with any real "power") is blighted by the wanton use of the veto by its permanent members to protect their "client" states even when those states are committing mass atrocities. And it doesn't help that the country fighting the most wars has a veto power.
"3) If they get too testy with the US, the US will just boot them out from the UN Building and turn it into a Holiday Inn. There's been a lot of calls in Congress in the past for booting them as well as the several times the States withheld payments."
Typical US foreign policy (dominate them) and diplomacy (if they don't do as told, threaten them). If the US does boot out the UN there would no shortage of countries eager to host it considering the economic benefits it brings.
"Which is just a load of hot air because all the governments involved carry sovereign power. They are each their own highest authority so answer to no one except another sovereign nature, and only if they butt heads."
Where countries have signed and ratified international treaties they are expected to be bound by those treaties. So in theory governments have to also answer to those treaties that they have signed up for. In practice the powerful countries have trampled on the sovereign rights of weak countries, and at the same time disregard the international laws to which they have signed.
"The UN does not have sovereign authority, and if it did it would by definition usurp sovereign power from everyone else."
The UN only has the powers that its member countries assigned it. And the only real power that it has is the UN Security Council which is the only body that can enforce (some types of) UN resolutions. But the ultimate power of the UNSC lies with its 5 permanent members, which in practice means the US/UK/France - because those 3 have been the most persistent in throwing their weight around and abusing the UN for their own gains.