I agree with all of this.
After reading lots of history, it seems to me that the most enduring and effective form of government is the decentralized imperial republic. This is not a common viewpoint among non-historians, but the key elements of this form of government tend to produce healthy, growing, prosperous, safe societies. Here's the specific elements in more detail:
Decentralized means allowing local areas in the republic to set largely their own laws, have their own worship, and their own customs. The head government sets minimum standards, and local governors see to it that they are met. These are basic conditions of infrastructure like roads and hospitals, communications networks, defense/garrisons, a few universal laws, and taxation. Everything else is up to the local regional governor.
Imperial will be the most controversial element of this, because there's been a large movement for self-rule in the post WWII era. I think there's lots of merit to that movement, but I wonder if the baby has been thrown out with the bathwater to some extent. Imperialism works as a natural check and balance against corrupt government - in a world where imperialism is more acceptable, it's basically "fair game" to go conquer any dysfunctional place. Thus, you don't get governments like you have in Venezuela with the government bringing in trillions in oil money that supposedly belongs to the people, but 1/3rd of the population are living on less than a dollar a day, and then the country has one of the highest murder rates in the world and the government is basically a mafia. In an era where imperialism is acceptable, Chavez gets exiled or executed, and the Chinese or Americans or British or whoever install a local governor that brings peace, stability, infrastructure, and rule of law to Venezuela.
Republic means some form of representative democracy. I think representative democracy actually performs worse on average than monarchy because corrupt, waste, and crime gradually increase in republics until the nation breaks, and it's very hard for a single leader to clean house. However, republics don't fall under the trap of having one horrifically bad leader who ruins the entire civilization. It's a tradeoff. I thought the British Empire did a good job with this, with a balance between the House of Lords, House of Commons, some strong constitution-type documents like the Magna Carta, the military, and local governors. Power was distributed in a decentralized way. The Prime Minister or Monarch could step up and assert authority when times got dire or massive house cleaning was necessary, but most of the time the Empire had some significant republican democratic elements to it keeping the aristocracy in check.
Of course, this is all very unfashionable these days, and everyone compares ideas to the current era. But for producing high levels of science, commerce, invention, quality of life, safety, peace, rule of law, health, art, and other key things - decentralized imperial republicanism has absolutely outperformed just about every other form of government.