No one size fits all
Knowing myself has been the biggest driver in my own productivity journey.
A lot of it boils down to energy states. There is the when and the what. You may not know the why.
As fleshed out in Daniel Pink's When, your chronotype is essential in understanding if you are timing the difficulty of your tasks to your energy level throughout the day.
For example, an early bird or lark would get her energy in the morning with an anticipated dip in the afternoon. You wouldn't schedule your most cognitively difficult tasks in the afternoon and expect to feel accomplishment.
For a lark, she can really reduce her guilt (whether it is mommy related or otherwise) by timing the bottom feeding tasks of life in specific parts of the afternoon (e.g. finding the most optimal credit card for personal finance optimization).
Then there is the matter of what is it that actually makes you feel alive.
This can take a lifetime. The things you thought you wanted weren't really that important. Or the things you actually did want in the past, you've now outgrown.
After there is a solid understanding of what and when for you, your productivity is going to ramp up markedly independent of someone's system or advice.
That's because productivity is highly personal and individualized.
There are so many productivity systems and concepts out there. We will explore different benchmarks and thinking throughout. Sometimes these thoughts are at odds with each other.
Everyone has their own unique prescription.