There were a lot of compromises and supposed safeguards made in the Constitution that have really come back to bite them. Most were made in order to get states to ratify the Constitution because 9 states out of 13 had to ratify it for it to take effect.
The bicameral legislature was to get both large and small states to agree. The House of Representatives was created to get larger states on board by giving them power proportional to their population. The Three Fifths Compromise comes into play here for determining population to get states with a larger enslaved population on board (superseded by the 14th Amendment). The number of representatives is not fixed in the Constitution, only that it be proportional to population but federal law has it currently fixed at 435. The Senate was to get small states to agree by giving each state two senators.
The Electoral College was created as a layer of abstraction above the voters and here's where a lot of problems have since been introduced. It was originally created because many people back in the 1780's couldn't read, so the people drafting the Constitution thought them to be too stupid for direct democracy. The Electoral College is defined a number of electors from each state which is the number of senators and representatives the state has. This means that the number of electoral votes per capita increases as the state's population decreases and campaigns take that into account.
In 48 states, the electors are assigned in a "winner take all fashion". Whichever candidate wins a plurality of votes wins all of that state's electoral votes. Nebraska and Maine give two electoral votes to the overall winner of the state and one to the winner of each Congressional district.
Electors are supposed to vote for the candidate chosen by their state, but that doesn't always happen. Those who do that are known as "faithless electors" and 33 states have laws regarding them, but none have ever changed the outcome of an election. The biggest impact they have had was back in 1836 when it caused a tie in the vice-presidential election.
But what about DC? Well, the District of Columbia didn't exist until 1791 and didn't have electoral votes until 1961. The 23rd Amendment says they have as many electoral votes as the least populous state (currently 3). They still have no senators or House representatives and their district government is Congress. Yeah, it's weird.
So now how does that affect us? Less populous states have greater voting power per capita in both the House of Representatives and the Electoral College. This gives them greater control over laws that pass Congress (a bill has to be approved by both houses), and an oversized influence over who will become President and Vice President. This body also has the power to impeach someone, which is analogous to charging them with a crime) This sounds pretty bad already, but wait, there's more!
You may have heard of Congressional hearings. Congress can compel people to testify in front of them as long as it serves some public policy purpose. Lately it's been used to call companies out on the carpet to explain why they shouldn't ban whatever harmful thing they're doing. It's also been used to launch investigations, which may or may not turn into an impeachment later.
Now we come to the executive branch, which is defined as the president and everyone in his administration. Pretty much every government agency you've heard of is in the executive branch. Congress was granted the ability to delegate determining the details of bills to the executive branch. Over time, they've used it more and more. The President appoints Secretaries to each of the cabinet offices and federal judges to their posts so long as the Senate confirms it. The flaw here is what happens when the Senate is tied. Someone has to break the tie and that is the Vice President. So less populous states have a slight edge here again in those rare circumstances via having oversized power in selecting the Vice President.
And now we come to the current issue regarding the Supreme Court. Supreme Court and federal judges are defined in the Constitution to have no term limits. They leave the bench when they die, retire, or are impeached and removed. It however does not define the size of the court beyond there a Chief Justice among them. The Judiciary Act of 1869 has it set at nine but it can be changed by another federal law. Any vacancies are appointed by the President and confirmed by the Senate just like if they were a normal federal judge. This is how we got into the predicament the US is in today. If the President and majority of the Senate are of the same party, they can fill any vacancies in the court with justices that follow a similar political ideology. That affects cases brought before the court for up to 40 years and those decisions have the force of federal law!
So that's how decisions made back in the 1780's got us to where we are today. It's a lot like a road. Over time, time, heat, and weather form cracks and holes in the surfaces, wearing its way all the way down. Eventually patches can't fix the problem anymore and the whole surface has to be torn up and repaved. The question is how bad things need to get before that occurs. Will things be passable until then or will everything be destroyed before that happens?