I'll take another bite today
I'll try to answer your questions with my view - but they are very hard questions to answer.
Most of the large problems are difficult, or they would already be solved. Politicians are not always motivated to solve divisive problems that they get political energy from, while they will routinely promise easy answers to intractable problems.
I would say a good balance between labor and Capital would be such that the country is politically stable AND business investment is encouraged.
Political stability is always desirable. We are seeing even foreign nations invest resources in destabilizing democratic western governments.
Economic growth has been identified as a general benefit to society. There are multiple economic machinations in place to encourage growth. Among these notable are marginal reserve banking, and limited liability corporate structure. Fractional reserve banking probably predates the US, but the limited liability corporation appears to be a 19th century US development (england passed a limited liability act decades later in 1855). While it is human nature to want a bigger piece of the pie, we should all agree that making the pie bigger is good.
When Capital has too much power, wealth inequality increases.
I suspect you are conflating "capital" with management or business operators. The actual capital routinely is coming from a third group (stock market investors, venture capital, etc). It is an easy argument to make that wealth inequality is at least in part being driven by automation and AI. Technology is allowing us to manufacture more with less human involvement, logically their share of profits is proportionately reduced.
As wealth inequality increases there is more and more class warfare and several times in history it has led to revolution (Après moi, le déluge).
class warfare is popular because there are less really rich people, so they are easier to marginalize. Revolution has multiple causal factors, typically self-determination (like our revolution against great britain). Perhaps the french revolution could be characterized as having a excess wealth component but they included others (liberty, equality, fraternity... no not frat houses.).
But on the other hand, there should be a balance such that the risk of investing Capital & starting businesses is sufficiently rewarded, i.e. so someone working in a field for a competitive salary might make the risk of starting off on their own for a greater reward.
Not necessarily rewarded, but should not be discouraged or hampered. It is sad to see reports of kids lemonade stands shut down by overactive local regulators. Most kids of my generation routinely traded labor for cash, cutting grass, shoveling snow, etc. It is sad to see entrepreneurial instincts nipped in the bud.
The price of labor is determined by supply and demand in the absence of collective bargaining (i.e. unions) or regulations (i.e min wage). Capital has more power if they tend not to be squeezed by tight supply or higher demand. For instance, if there is increased supply made available to counter rising wages (H1-b visas for example) or demand can be reduced in the face of higher wage demands (automation, etc...), then Capital increases power.
Supply and demand is alive and well in labor markets. Despite advancing automation, some industries are desperate for capable, affordable, workers. Sometimes distorting the markets with regulations (like minimum wage) causes unintended consequences. I expect to see more and more automated burger flippers to replace human burger flippers that customers won't pay for.
This is an old discussion but elevated minimum wage makes the bottom rung of the employment ladder too high for unskilled entry level workers to reach. (my first minimum wage job paid $1.25/hr and I was probably barely worth that at first.) Minimum wage jobs should be entry level jobs to help people get into the labor market and move up the ladder. They were never intended for head of household to support entire families with.
No, it's valued at the price it can be obtained for through supply and demand. For example, if you wanted to hire someone to renovate your house, which would require 100 hours of labor, and the value of the renovations would increase your homes value by $30k, would you hire someone at $300 an hour? (100 hrs*$300/hr=$30k) I don't think so - if the going rate for carpenters was $50 / hr, you would hire someone at the going rate $50.
Most self-employed carpenters work like subcontractors, sometimes you hire them by the hour, sometimes for completing a task. I have some anecdotal experience. I recently hired a carpenter to repair some water damaged roof soffits. He quoted me an estimate of $100 hour, for two men (him and a helper), and materials. I settled up with him two times over the course of the work and both times were well under the $100/hr ballpark (under promise, over deliver.) I am now contracting the same guy to put a new tin roof on my house (single entirety bid). In neither case did the value created have anything to do with my hiring decision, it was about my ability to hire a skilled worker locally to do the tasks required, when desired (I had to show some flexibility to accommodate his availability).
I have been up on my roof before in the summertime, I do not plan to repeat that experience humping around big sheets of tin roofing.
Cost vs value created is more of calculus performed by house flippers to improve profitability of a short term transaction. Typical home improvement is rarely driven by purely rational calculations, while some home improvement loans may look at it (but bankers mainly care if they can get paid back so probably decide based on equity in the home).
Business works the same way. A business employs people that create value that the business realizes for a profit. The lower the cost of labor, the more the business & Capital profits.
True but labor is only one factor, and increasingly not the dominant one (maybe is for service businesses). Back in the 1980s electronic assembly automation gutted the business model of my kit company. It was Japan then, not China, but I saw the writing on the wall, when name brand commercial SKUs were selling for less than my unassembled parts cost me. My kit company customer's assembly labor contribution became worthless.
Attached chart shows how capital has become more profitable while worker's share of $$ has declined.
Again IMO conflating or mischaracterization. Capital is passive but can be used to do good or bad. The limited liability corporate structure was set up to empower this capital to be put to productive use, no doubt creating many decent paying jobs over the centuries.
Now unskilled labor (I dislike thinking of anybody as simply labor, because that means they are in line to be replaced by robots). Anybody with half a brain needs to be stretching as hard as they can to acquire merchantable skills. Right now truck drivers are in demand, but don't plan on retiring from that gig. It is only a matter of time for self driving trucks to take that job.
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To get back on topic of finding a solution, what is the ideal remedy? I don't see capital as the problem, but perhaps a target for providing the easy solution, ie wealth transfer using government force... (wasn't that a factor in our revolution? "Taxation without representation." ).
Simply transferring wealth can not happen without unintended consequences (mostly bad IMO). We need more education of the right kind (not free college and/or saddling students with huge debt for an education they can't apply). The future will surely be different, and keeps changing. We can agree that the future looks less rosy for unskilled labor...
Let's work to get them skilled up, with skills they can use to create value for themselves and others.
JR