Thanks, Richard, for your appreciation and for sharing your "rules of thumb". In my experience, the stress level is often the most difficult aspect to control. What's helping me in that respect is Zen philosophy. I have been trying to practice it for the past 30 years ("trying" because I can't claim to master it). It's the daily micro-dosing on koans and concepts that does it for me. And as Marijke pointed out, exercise does a great job, too, in reducing stress levels.