@Martin, I am already very competent in Python (I also prefer it to C#). But between Python and C++ I feel more at home with C/C++... and the pain it comes with :)). So its not about me. This is about Aki.
But speaking from personal experience, what is simple to one person may not be to another and that's the whole point I am making. Python is "Relatively" simple to learn, yes. The key word is relatively.
It also depends on what you are creating. It might be simple in any language to make a "hello world" app. But to write a flight navigation system in any language regardless is whole different matter. But thats not the point.
So anyway its Aki's choice that's why I advised him that if he feels he would get things done quicker in C# than he would if he starts over with Python then he can make the decision he sees fit. I know from historical mails here Aki is enthusiastic about C# so personally I'd rather he stick with it and maybe in 5 years he will be my preferred C# mentor :)