This site frequently refers to Producers and Leeches. Optimizing away leeches is an important Pillar of Economic Optimization.
First we should define Producer. A Producer is a person or company who generates genuine value (wealth) in the economy, making peoples' lives better. It's as simple as that. A leech is pretty much everyone else -- someone who sucks value from the economy. A leech might not be a bad company or person, but its role shouldn't be needed in the long term. The sooner we can turn leeches into producers, the sooner everyone's work week can be shortened.
Let's go over a few examples on how to think about this:
I'd have to say leech, because I believe they can be largely if not fully optimized away. I can easily envision a restaurant that is run entirely by robots, from receiving food deliveries from automated delivery trucks to cooking the food to serving it up.
Leech -- automatic payment acceptance machines are maturing and getting more widespread use every day! And this is a good thing.
Also leeches, as the vast majority of this should be fully automated.
Leeches -- all of them! As noted in the Pillars page, benefits of having only automatic cars on the road are absolutely astounding. If we want an optimal economy, we can't let this one slip away!
And now we get to the producers. This is what it's all about! These guys will make all the good stuff happen. We need to just make sure they're not overworked, so that as many people as possible can have this profession, and when they come to work (for their short week!) they're relaxed and ready to go!
I would consider these to be the residual roles for humans in restaurants, stores, and factories; they would be producers also. Their roles would be to ensure that all the automation keeps going smoothly. Great role for those who are not building or programming robots.
If "teacher" means "lecturer", then definitely leech. Quality lectures on any subject can be had for free on the Internet. Re-thinking education and optimizing away expensive schools will be a huge win. (BUT: Not at the expense of education! Having an educated next generation is perhaps the very top of my priority list. My contention is that true education can be had in better, much more economically optimized ways than huge schools.)
Producers -- this is what "teachers" should become. A good tutor will help students understand and apply material in lectures and work with the students to help them achieve something great with the material they have learned.
Producers, certainly, with the note that as people take their health more seriously, doctors should be less busy.
Leech. Appointment scheduling should be fully automated, as should importing of a patient's personal information and medical history (with care and proper use of cryptography, I can envision a way that this can be done while fully taking privacy into account). Even doctor's assistants should be much less necessary as many tests can be automated with newer technology.
Necessary in our current economy, but really should be needed much less in an optimal economy. After optimization I think there will be a small role for them. So mostly leech.
Producers insofar as they are fighting real threats to the people from criminals. Traffic cops are major leeches and will disappear with automated cars. It is also leechism to police victimless "crimes" like marijuana posession.
Well if we were being invaded by a foreign military, they would be producers. Any necessary training to prepare for that could be considered production. However, looking at the US "defense" budget, I have to call the overwhelming majority of it leechism. Policing the world simply squanders resources while making others hate us. Weapons are built that the military doesn't even want, due to corruption in Congress. Looking at how many uniformed soldiers we have, it is just very hard to believe that they are all doing necessary training work preparing for an invasion. (I will say they are brave folks and the best in the world at what they do, but bravery does not necessarily equal production.)
Ideally there would be no full time soldiers, but a lot of people training for defense in their soon-to-be-copious off-hours.
Leech extraordinaire. Throwing a frigging ball is not worth millions of dollars!
This one is somewhat hard to call. Of course construction is necessary, but how much of it can be automated with robots? I have heard of a house being built with a 3D printer, but I think it will be a few years until we can say if that is the way of the future. Of course, the fact that it is even imaginable today means that in a few decades, someone will have figured out how to do it.
Long term leech, I think. In an optimal economy where everyone is educated and empowered, how much social work will be necessary? Perhaps some, but I speculate a tiny fraction of what is done today.
Almost all leeches, because their "products" are newfangled ways to deal with money that, when you think about them, don't make a great deal of sense. There is room for some legitimate banking activities, but that is a relatively small part of today's finance industry.
The internet is a tool that can be used for production or leechism. Those who work on internet infrastructure, then, assume the leech/producer status of the project they are working on. However, even this industry has increasing automation and increasing operational maturity, so eventually there should be many fewer of them than exist today.
It's going to be difficult to come to widespread consensus on this one. A first world society needs to have reasonable protection from harm to the public due to malice or carelessness. But there have been plenty of reports of government inspectors going too far. Ideally, companies would police themselves, both because producing safe high quality products is morally the right thing to do, but because it also makes the most business sense -- producing unsafe products will quickly kill one's reputation. It seems also that government has mandated inspection on an increasing number of things. A few core inspections for building safety and food safety probably makes sense and therefore are producers. When it goes too far, they are leeches.
Again, widespread agreement on this will never happen. Taking a step back, I would say that religious actions have value and are producers if 1) they instruct people in genuine spiritual truth [and what constitutes that is what will never be agreed upon], or 2) they add other intangible value to peoples' lives or make hurting people comfortable.
One could imagine that with 10 hour workweeks, much more time could be given to serving with religious organizations by laypeople, perhaps necessitating fewer dedicated clergy.