2 flaws of capitalism
A barometer for any economic system's success is it's ability to increase happiness. Capitalism has been a successful system at increasing happiness, though it does come with flaws in it's purest form such as allowing monopolies and allowing companies to stifle competition. These types of problems are part of the two biggest problems in the most purest forms of capitalism.

Only thinking of your own interests

This is normally a benefit thinking of your own interests as it improves competition, but sometimes you are not the only person at risk from the actions you're taking. Imagine we allow companies to freely buy land, build a nuclear power station and have their own safety regulations. As a owner of the power station your risk is the profits of the power station, not of people who live around the power station. As you can see risk isn't just on the owner of the company and the people who buy the products.

Elk need larger antlers than their peers when fighting to find a mate, but the larger antlers actually make it harder to run away from predators, it would be in all their own interest if they all had smaller antlers as it doesn't matter how big the antlers are but how big they are to your nearest competitor.
This is the same case for certain companies when advertising, you have to spend more than your competitor on advertising but this hurts both your companies having to spend so much money on advertising, it would be in both your own interests to stop advertising in certain cases.

People not knowing what's in their best interest
There are two main reasons people make decisions that are not in their interest's. 

1. Lack of knowledge can make it hard to compare two products or to make a decision on if a product is right for you harder. To know if you are getting the best and appropriate healthcare can be difficult when you don't really know how to even compare what is a better healthcare plan. You may believe you have all the relevant information to make a decision but even then you can't be sure and it's in the companies interest to suppress information that would be harmful to it's profits.
2. We are not 100% rational beings, our brain's are wired up to want and act certain ways what can be detrimental for us and against our own interests, such as wanting to loose weight but having craving to eat more, wanting to stop smoking, etc. capitalism can play on our craving and the quirks of how our brain is wired up and actually make us more unhappy in the long run.  

Public opinion
It’s easy to forgot public opinion when it comes to making decisions on utilitarianism basis and how it is still a factor to our happiness.

Would it be right to kill one man and use his organs to save five other people? (Trolley problem)

If we assume by saving the five lives would result in more happiness, this seems like the obvious choice for any utilitarianist. I’d like to point out other people opinion’s that are not directly involved also play a role.
Would you like to live in a country that did this? I’m assuming you’ll say no, if enough people are unhappy about the situation this can counteract the total happiness gained to the population by these five individuals survival, so in a utilitarianist basis it would still be seen as wrong.  

Fundamental rights
Fundamental rights were a way of explaining about our thoughts on moral issues to ourselves and other people, if you feel against killing an innocent life to save five others you might say “It’s fundamentally wrong to kill an innocent person.”

This what happens in the Trolley problem, (watch video in link) when you give people the first scenario, they feel its right to save the five and they may say “It’s right to save more lives” you can ask them are they sure and they’d agree, though when you give them the second example they’d disagree and think of a new reason to explain their feelings in both examples. We do this to explain the reasons why we make any decision, there are thousands of psychological experiments were seemingly unrelated issues influence our decisions, it has been shown that people eat more under blue light but if you were to ask people why did you eat as much as you did, I doubt they would say because of the blue light, people tip more when it’s sunny, you are more likely to say yes when holding a hot drink than a cold one, this type of psychology is also on display if you've ever tried to define works such as "game". So if people just slightly makeup reasons why they think something is right or wrong what should we believe?  

Summary
I don't know if fundamental rights are right or wrong, fundamental rights don't have to give you the best solution in every scenario but it has to increase happiness in the long term and any system that would increase happiness faster would trump the one proceeding it. I have no idea what systems of governance or in society increase happiness, though I do think happiness is what we should be basing it on.    

Measurement of happiness

If we had a machine that could make predictions on how to increase future happiness, what would it’s measurement of happiness be?

• Total happiness

If it measured total happiness, it could lead to a result were we are all more unhappy but there are more of us so total happiness has increased. The mere addition paradox.

• Average happiness

If it was to measure average happiness, the machine could make decisions to kill anyone unhappy to increase the average happiness.

Both measurements don’t always give satisfactory results, so is there a measurement that can overcome both these problems?

• Total happiness with exceptions

If we allow the machine to make decisions to increase long term total happiness, though we add an exception in that it can only add new people if by adding those new people it increases long term average happiness.

Though still hardly satisfactory in that it’s slightly too complicated to be taken as an axiom and you can always still argue some results are not moral and it would be hard for me to disagree. What also makes me feel uneasy is should 0 be neutral or total unhappiness, if we started considering unhappiness to be in negative numbers you get many more unsettling events we would have to assume to be normal and okay morally. I want to do some more research on the the cognitive neuroscience and other aspect of happiness and hopefully when I feel I can turn this into practical advice you will see more blogs.