3. 'Free' is not a proper adjective to represent freedom.
It is the best adjective available for the purpose in the English language, so that's what we use. It is also the term we have been using for 20 years, and changing now would be a major problem.
4. The usage of 'Linux' for 'GNU/Linux' is justified for ease of use.
It is true that 'Linux' is name of a kernel. However it is more frequently used to represent the 'GNU/Linux' operating system.
To call the system "Linux" hurts our work, and undermines all our efforts today, by suggesting to the public that the operating system we principally developed exists due to Linus Torvalds' apolitical engineer's world-view. That world view would never have produced a free operating system because it does not consider freedom a goal.
"Ease of use" can hardly be a sufficient reason for giving to another philosophy the credit for the work that our philosophy brought about. If you want to cooperate with us, please call the system "GNU/Linux" and recognize our work.
If you feel that you need a shorter name, the most appropriate one is simply "GNU". That is the name we gave to the system 20 years ago when we started developing it. It is shorter than "Linux" also, and shorter too. (In the FSF we prefer to write "GNU/Linux", partly to give Linus a share of the credit for the part of the system he added in 1992.)