That said, I think biggest mood/focus/energy difference (besides a nice workout which is also important) for me was getting vitamins and other micronutrients in order. I highly suggest you to do a blood test or two per year for all the common vitamins/micronutrients to see which you need to fix.
For men, I think it is especially important to get magnesium, vitamin D and zinc in order; lack of any will likely affect your testosterone levels negatively which will then screw you up in many more ways.
For example, way back I had critically low vitamin D resulting me in frequently getting sick and having periods of complete lack of energy; fixed that and I did not even get common cold for a long time, also no longer random days with no energy.
You shouldn't overly rely on nootropics, caffeine+l-theanine or other supplements to cover up base deficiencies with your micros.