Good points across.
Working intensely focused on a few tasks is repetitive and can be exhausting over time. It's like the exercise when you stare at an inverted image for 2 minutes, then look at a white wall, and you see the picture clearly. That's what happens to our visual receptors, we become overexposed to the same stimuli and our mind craves a dose of variation.
I agree with finding some time for breaks with smaller projects. If we are not at our 80% - 100% best, we are not going to be efficient. Similarly I save down inspiring artworks in sorted folders so that I can let my mind be refreshed by other people's quality pieces and get some perspective.
Creating a mood board and/or a reference board is time well invested. When we place relevant reference images together in a collage we start to connect different ideas in new ways. Observation is also a part of the work process.