Understanding can't just be transmitted through words, and requires introspection. Congratulations on your epiphany!
I optimize life for happiness. I try shape my life to enjoy the process like you said: good work-life balance, doing something that challenges me just enough on average, that I enjoy, with people I enjoy.
I try to bring that to my teammates and actively contribute to a culture of zest for our profession at my job. Why? You're happier when surrounded by happy people. If you're surrounded by people doing the same, it's less likely for culture to change in a negative way.
I mentor teammates and grad students. Helping others grow makes me happy, and especially during the pandemic it's been a good way to stay connected to others.
There will always be rough moments, but there's no happiness without pain. It requires constant maintenance: keep yourself healthy, your mind stimulated, your body exercised, your social skills challenged. Make time to also stop and enjoy doing nothing.