I disagree on every point, especially if this is addressed to students starting out for the first time. '
The teacher of a beginner-to-intermediate must be a specialist in this area. This teacher establishes every basic foundation at a time when not a single one exists. It requires a certain kind of mindset, awareness, an ability to organize your teaching around this priority, to observe and problem-solve. There are excellent teachers in this area who are also concert pianists, and many more who have not decided to pursue that career.
Any well-rounded artist will know the musical matter in the the way needed to deliver a top-quality piano lesson.
The "musical matters" can be such things as "bring out the melody", "highlight the important notes, listen, like this", "pedal more subtly". A piece of music may be assigned - maybe first demonstrated by this teacher for how it can sound - for the student to take home and practice. To do any of things, the student first needs the TOOLS, and these should be developed by a primary teacher whose value is greatly undervalued, and whose work is often misunderstood.
There are boring and mundane things like learning to sit and move in a comfortable position. Learn to read music and what that entails. How to develop even a small piece at home in practising, and how that practising is done - having this developed over time. Very often the musician who can teach you a myriad of interesting things about the music does not have the patience or the character to develop those kinds of skills. Nor the expertise. His expertise lies elsewhere.
It is the adult student who suffers from this the most, often going to a lofty institution in the hope of getting good instruction, looking for a teacher who is a performer, and then lost and over his head because he is being asked to do things without having been given the tools.
If you find a super talented pianist who teaches...
The word "talent" is much too vague. If he has talent in teaching itself, then perhaps. However, the word "talent" connotes a raw potential. In a teacher I want someone who has developed knowledge and skill. He must bridge two worlds, and giving basic skills is the first priority for me.
After years of trying to find out the best way to go about it ....
Did you spend years trying to find a good teacher to teach you at a fundamental level? That is not possible since you learned since childhood, and I think you had good teachers from the start. Or do you mean that you spent years trying to find a good teacher at an advanced level? Your guidelines may indeed help someone who is looking for teaching at an advanced level, someone who already has basic skills solidly.
By coincidence, I did spend years looking into finding a good teacher at the elementary level. My guidelines and conclusions are very different from yours.
. Who can be better to teach you than someone who knows music to perfection?
It is a fact via the experience of a number of people whose stories I know that knowing
music to perfection does not necessarily relate to knowing how to develop a student from scratch.
The same intelligence artists apply to their performances can be applied to deliver wonderful teaching. Why?
Because you need to be very smart to be able to position yourself in the place of your student - to try and think as he thinks- ....
No, there is more to it than that. There is specific knowledge to be applied, and experience in a particular area.
Have you ever taken a lesson with a real concert pianist
Yes.
One who also has expertise in teaching, because he has spent years and decades looking into this and honing it, specifically.
. I wouldn’t suggest to go for someone who is not doing very well. Why? Because, that professional would do whatever he considers necessary to keep you as his student.
I disagree on a number of counts. First, we can say that a number of charlatans do very well, because they know how to market themselves, how to go toward what is popular, and what sells. They know how to bluster and fool the public. Secondly, I have personally worked with several teachers who were doing less well financially because of their integrity, because they did not play the game. The bottom line is that financial success or a reputation in neon lights, neither of these things are an indicator either way of good teaching ability. The only way to tell is by observing. This starts, as a student, by getting enough knowledge yourself so that you don't get taken in!
If you find out your teacher is delivering 10 hours of teaching every day, then you are in trouble. No artist can keep up with that sort of schedule. Teaching is very energy consuming. Your teacher needs to be a well-balanced individual who has a musical discipline and therefore can teach you how to develop one. It is not advisable to deliver more than 25 hours of solid teaching. Basically because after that, it stops being solid teaching...
I do tend to agree with that.

5. Recordings
Everyone looks great on papers. For that reason, you need to check if your teacher has any professional recordings published on the internet -Youtube, Vimeo... It doesn’t matter if they are ancient, but at least you should find something there. A good pianist will always has a comprehensive collection of professional video recordings online to promote his own artistry.
No - I disagree. I'm not looking to hire someone to perform at my venue. I'm looking to be taught. I have watched recordings of excellent artists who also taught and also featured their students' recitals - some of them show up major teaching flaws in the essentials I wrote about. I have also worked with some very excellent teachers in recent years who do not feature their playing on Youtube. And no, a good pianist
does not always have a collection of recordings on-line (professional or otherwise).