250bpm

Most people are inclined to work even if they don't have to(For example, linux and wikipedia). Non-scarcity economies can grow very large(Again, linux). About 10% of the populations are professional slackers, and they already don't work or work little for meager salaries.

My guess is that basic income will cover basic needs(house, clothing, food, internet, …) and people will work on interesting things to obtain expensive "material/non-material" stuff(a jet engine, ticket to the moon, social status, knowledge, quality time, etc, …). Then, basic income will basically just remove neccecity for "subordinate" jobs but encourage people to work as free agents or in small companies doing interesting things together without managerial interventions.

What if people are mad for your pictures, but don't give a shit about your music? What's the mechanism to let you know that you should focus on the former and let the latter be?

In traditional economy you are guided by prices.

In economy based on basic income there's no such mechanism.

Maybe producers should actively search for feedback as a way to improve their credit (you get more credit for nice pictures than for sucky music). Would that be strong enough incentive to drive the effort in the right direction? Or should it be enforced by voluntary redistribution (donations)? In the latter case, wouldn't it mean that those working in scarcity-based sectors of the economy would have more say than others?

In fact, we don't know. We don't even have a way to reason about such things. What's missing IMO is a generalised economical theory that would take non-monetary aspect into consideration rather than conveniently waving if off as "externalities".

• Preface
  
  I must have been misleading about how I want to make money and enjoy hobby. With or without basic income, I plan to make money mostly by writing programs and to enjoy drawing pictures and composing songs as hobbies. So I start with hobbies.
  
  
• Hobbies are more about consumption than about production.
  
  When people draw pictures and write songs for fun, people generally don't care much about how badly others want their talents in hobbies. It's because hobbies are more about consumption of time/material than about production.
  
  In other words, most people generally pay money to enjoy hobbies. However, if other people praise them for their drawing talent, they will be gratified and do more drawing than writing songs, and vice versa. If they get good enough to be paid for one of their hobbies, they might think about making money from it.
  
  
• Non-monetary wealth
  
  There exist non-monetary wealths. Monetary currencies are preferred forms of wealth because they are easily convertible and fungible. Although non-monetary wealths are also valuable, they are generally not easily convertible to other forms of wealth.
  
  
  1. social currency
     
     According to pieter hintjen's recent book, "Culture and Empire", the US government spent millions of dollars to make people click "like" in facebook. Social currency exists. Hobbyist artists are gratified and release more artworks if others click "like" or praise them(social currency). That process also generates reputation(social currency) which can be converted into other personal properties later. Amazon book reviews are a form of social currency, too. So, social currency can incentivize people to do more of something. However, it takes time and careful planning to convert social currency into other forms of wealth(food, house, etc). Thus, if people put above-board efforts into earning social currency for a long time(half a year?), they'll get burned out. Basic income changes this dynamics, which will be described below.
     
     
  2. Skills
     
     For example, I and you have skills as programmers. Skills are non-monetary wealth that can be converted to monetary wealth easily if other people want those skills.
     
     
  3. Body(Health and beauty)
     
     Health is a form of wealth. Japanese have the longest expected lifespan, and japanese people are considred to be wealthy not just because of their per-capita GDP but also due to their life expectancy. In Congo-Kinshasa, the life expectancy is about 50 years. Beautiful people monetize their beauty in markets.
     
     
  4. Human coin
     
     According to "Culture and Empire", when money didn't exist, there wasn't a barter economy. If I give you milk when you starve, you owe me. You repay the debt by giving me eggs when I starve later. Ledgers of human coins are maintained in human minds, so human coin economy doesn't scale. Monetary currencies solve scaling problem and remove human coins.
     
     
• How I guess you think BI(basic income) blocks market information flow.
  
  I guess you have one of two possibilities below in mind, and I have arguments for them.
  
  
  1. basic income increases tax too much that most of people's earnings go to basic income, distorting markets.
     
     Brazil adopted basic income years ago, and they are not heavily taxed so far. Switzerland is voting for unconditional basic income of 2800$/month for every adult employed or unemployed. I don't know about switzerland yet. Even, south korea, my country, can implement BI if the government cuts out wasteful programs(S.Korea has many) and consolidates lots of welfare programs into BI.
     
     
  2. BI incentivizes people to ignore market signals because people can subsist without jobs anyway.
     
     I guess it's possible to configure BI to incentivize people to ignore market signals. However, I think it generally makes people more sensitive to market signals. I'm going to explain my rationale below step by step.
     
     
• Psychological effects of basic income
  
  My father arranged a private basic income system for me via some financial vehicles, so I know what BI does to mind. Almost nobody is satisfied with basic income that only covers the most basic needs(house rent, food, clothing, internet), and they need to trade in markets to get what they want. BI just guarantees that people still have comfortable low class life if they lose a job. This private BI urges me to drop my job, endure months/years-long unpaid learning, build reputation, and make living as a free agent like you do, and I'm actually going to do it. In other words, BI makes it bearable for people to quit crappy jobs and live on ramen noodles for years in rent houses until they get a decent job, become a well-paid freelancer, or one of their tablet games raises them to a middle class/upper middle class life.
  
  People will be inclined to refuse crappy jobs, and this leads to some economic effects.
  
  
• Economic effects of basic income
  
  If basic income taxes people too much, it'll distort markets. If it doesn't tax much, private sectors will always have abundance of money to trade with or without basic income. And I think many governments can implement BI while increasing tax only a little by cutting out useless programs and consolidating lots of "conditional" welfare programs into "unconditional" BI. Also, unconditional BI is simpler to maintain and think about than lots of "conditional" welfare programs.
  
  Central authorities hire managers, and managers hide market signals. Workers actually feel warmth in the shielded core and are happy without market signals. Since workers don't know how market actually values their labor, they don't know if they are compensated fairly or unfairly. Those workers without market signals don't know what societies need in the long term. However, managers don't know what societies need or want in the long term, either. So centralized corporations tend to make irrelevent products.
  
  Since people with BI are more inclined to refuse crappy jobs than without BI, it encourages people to leave established companies. Many more people will endure months/years-long unpaid learning and become freelancers or join small startups. Some people will opt to build other non-monetary wealths for months/years, and they may or may not convert non-monetary wealths into other personal properties(house, car, food, etc) later. It means basic income favors decentralization. If workers are inclined to become freelancers, join startups, or join open-allocation shops(github, valve, …), they'll become much more sensitive to market signals. Even if they choose to build non-monetary wealths mainly, they are not shielded from market signals as long as they communicate with other people. Managers would do a much better job at shielding market signals.