When we think of productivity, we often think of a tool, app, or service to make us more efficient. What we forget is our body is the ultimate productivity tool.
I can relate to this too!
There is a period between 20h and 23h where I do so well! And early morning also!
I know you already have a massive list of books to read; is "The Power of Full Engagement" on it? The first paragraph is entitled "Fully Engaged: Energy,Not Time, Is Our Most Precious Resource."
Great article! For me, morning is definitely the most productive time of the day _and_ I have seen time and time again how energy affects flow / productivity. I'm now quite comfortable in acknowledging that a particular task can be put off until I have energy (which is probably some upcoming morning) and that helps to reduce stress and manage expectations. As you've already read in "Sleep", managing your first waking hours with useful things (not email, etc) is a great idea :)