Balsa flies better than Foam
On many occasions, it is true BUT what is not said is that Balsa is also MUCH more fragile than foam, so the trade of, for a 1st plane is clear. Get something which has the strongest structure possible.
 

If you don't build your plane, you won't learn what it takes in this hobby
Absolutely wrong. You will just not learn how to build, but you can still be the best pilot in the world, and have the biggest fun, without having build 1 plane.
 

Electric Planes are less powerful than gas planes and therefore more difficult to learn with
The 1st assessment is somehow wrong and the second entirely wrong. Electric planes can be as powerful as most Thermic planes, and their design, their weight and structure makes them actually MUCH more suitable for learning. More and more people, who want to learn how to fly, actually start with a cheap electric setup and... Then remain in electric after they see how nice and more enjoyable it is for them. Some others will prefer Thermics, as indeed very powerful, and makes noise and provide a real engine, which some people prefer. Also, most of the biggest planes seen are for now Thermic.
 

Computer radio are worth it compared to regular ones, as more powerful
Yes, they are more powerful and cost more to start. They also offer more flexibility as to enter few different planes. Also, if you plan to resale it, chances it will be easier to sell a computer Radio than a non one. So if for a similar price, you could get a great deal on a Computer Radio, then go for it as it offers indeed valuable options. If not, a Standard Radio, with 1 plane setup, elevons, servo reverse and should serve you well.
 

If you learn alone, it will take you much more time than if you learn with an instructor
True, but it depends a lot on you actually, and how you can learn. If you have the patience to read, and understand well, and if you follow certain steps, SOLO, you will be eventually perfectly fine, regarding time and learning. Fine, but not as good as if there would be indeed an instructor with you. Looking at your mistakes, and telling you how to correct them. So yes, an instructor is better in general, but you can learn SOLO, certainly with few mistakes here and there, but nothing critical, if you follow a proper way like the one mentioned here but there are many others written many places.
 

If you learn on a simulator before, it will make a huge difference in your learning curve, and will save you lot's of money due to the avoided crashes
TRUE, so much true. FMS is for example a free Simulator and following proper learning steps with it, you can learn and do your mistakes and try all kinds of maneuvers, on the simulator. Lot's of money saved and countless stories of people who flew an eventless 1st flight, after having spend 5 to 10 hours practicing on a simulator before.
 

Better to buy from a Local Hobby Shop than from the INTERNET as you then get Services from the owner of the shop and some levels of warranty
Depends very much on the owner of the shop. For sure, during the buying phase, anything will be promised. Reality later on is not always there. Some owner have no time anymore to teach you, have not a lot of time to also help you if you plan to build it. Of course their interest is to keep you as a customer, so most will be helpful, but be aware that the sky is not as dreamy here. Lot's of people got disappointed. Best is again to have someone who is in the hobby, to ask, local, or virtual, on on the Ezone Forums or other local forums, within the country you leave in.
 

Small planes are easier to manage than bigger ones
Don't think so. They are usually more nervous and more sensitive to the wind, and more difficult to spot, if they go just a little away from you. My personal preference for the wingspan to start with would be around 1m (39.4 Inches). Not too big, not too small, and overall stable with some small wind.
 

Foam planes are unbreakable
Not true. They break much less than Balsa planes but they also break, in certain conditions. What is also important to understand is that even if the outside remains sometimes not too damaged, their internal parts are as for example a heavy battery will just be like a bullet breaking everything on the way, during the crash
 

Mixed, Foam and Balsa, planes take the best of each world
Could be true. Difficult to give an answer to such a general statement, which you will hear time to time. It depends which parts are in Balsa, and which ones are not so here, I would just advise to understand the physics of the structure and apply common sense. Just think about a crash, after you understood the structure and you should be able to anticipate well its strength and weaknesses
 

Better to learn with a landing gear than without
Not true, better to learn with as little variables as possible. A landing gear will force you to land on certain fields, and with a certain angle. No landing gear offers much more easiness to select the place to land. Choose, for your first plane, one without landing gear.
 

A Trainer should be a plane that automatically comes back to horizontal, if you release the stick
True. These are the best planes to start with. One of the most important feature for a 1st plane. When you loose it, the feeling that you can just release the stick and in most cases, the plane will have the behavior of coming back to neutral flight is very securing.
 

Using a Gyro is not a good thing, you just don't learn well with it
Not true. You just maybe break less planes with it and you also sometimes could do without it, but Gyro, which will put back your plane to neutral flight, as soon as you release the sticks are worth gold ! A Gyro is like an instructor, which when you loose it, takes over, and it has the time, in most cases to do so. Is it better than an instructor, again, the answer is no, but it is much better than flying alone also. The down part is that they are expensive, so the trade of is how much money saved, as opposed as if you would break your plane. Usually, they are worth the money when you think of this. But again, many people could make it without, just you may loose more money than the cost of the Gyro, except if you break the Gyro on a crash, then you lost on all levels.