Hi, I'm the author. I submitted the article because I'm fishing for feedback. I'll be flying back to the UK from Pycon in a few hours but will try to reply to any / all questions and comments. Thanks!
The only thing I'd say is about your "extensibility" section. The value of this is a little abstract. After I learned programming Basic as a kid, I put it aside for a few years because I felt like I had "outgrown" Basic, and couldn't really do much interesting with it. Part of the value of Python is that it will "grow up" alongside your knowledge of it: you can program turtle graphics in Python when you're 12, or program your raspberry Pi, or build game mods, but then also know that you can use SciPy/NumPy when you go to college, or be able to use it in real, powerful applications.
How do you address Python 2 vs. 3 in advocating Python to kids?
I wouldn't worry too much about the pip and virtualenv tools. I would focus on learning the language, and building something that is interesting to you.
You will learn how to use pip, when you need to install a new Python library.
You will learn how to use virtualenv, when you share have 2 programs that use different sets of libraries, or you want to share(set up a dev environment) a program with somebody else, and you need to communicate the different requirements(libraries) for using that program.
