Yes, economists. You know what the problem is with economists? I studied economy, and it probably isn't the same in every country, but we learned a lot about the common economic phenomenon (inflation, primary emission, money, supply, demand,.... you name it) and what they can provoke. But we never did any serious case studies. We never learned a true picture of how those phenomena all work together in an organic society. I believe that a bachelor of economy should be able to predict an output model based on some input parameters, but guess what - we are not able to do that. Also, there are quite a few things they won't tell you, and also - you learn mostly about old ideas, nothing about new ones, so when you finish your study, you are already a couple of steps behind.
There are different economic models that describes how beautiful a country looks like when it follows. But the real is, there is no such thing as best economic model. All of it has its disadvantages and people specially the government and private organizations take advantage in economic system.
There is no dynamical system that takes place in our economy, most of it are just for a conspiracies to improve theirselves. We never functions as one, people never united because we have our own perception.
In conclusion, The wealthier person benefits all of the sacrifices of poor people and even there is communism that tackles the equal allocation for the people, the end of it will goes in the pocket of administrations. Remember, there is no equality in this world, rights are nullified by power!
I would not say that economic phenomena are all assumptions. For example. The phenomenon of demand and supply. They are really powerful and explain how the things happen in the real world.
The economic model is a sum of different phenomena and as you noted there is not "the best one". Each of the old models can be applied to a different society and wouldn't necessarily work on the other. However we can study why something worked out and something did not and based on that make new economic models, always having in mind what the current society needs.
The power of the greedy is what the problem is in every system. They will always find a way to make things their way. Hence I made an argument that blockchain and smart contracts can help stop it from happening with some in-built interventionism.