Setting ambitious targets and remaining zen - is it possible?

As a professional project manager, I pride myself on being well organised. I set and reach my goals in all aspects of my life, all while managing to stay on the right track. Up to that point, all is going fine. Overall, I'm happy with the results in both my personal and professional life. However, I find it difficult sometimes to be satisfied with what I have managed to complete during the day.

That's despite the plethora of methods and good advice available to me: being efficient and remaining effective, following the GTD method1, putting first things first2, managing tasks, taking time out for yourself, family and friends, practicing sport, eating well, remaining zen. How to not get snowed under with such a huge to-do list? How to not overload my days? How to be satisfied? Not always very obvious, is it?

I would like to share with you a 'light bulb moment' that came to me following my various summer readings. I realised that you can have two methods for evaluating your performances, one for "today" and the other for "the future".