Hi Tom, wow, great background and experiences. I love that you want to share and it’s a wonderful idea to write. There aren’t enough writers in the world and you would surely find a niche that would be drawn to you.
I’ve worked in marketing and online communications for more than a decade, writing has been a huge part of this wider field. So I simply call myself a copywriter now :)
You are right, it is a great art. I love studying it and practicing always to improve. What I’d say is choose writing and writers that you’re drawn to. Read their tips. Analyze their style. Use all that to write well and form your own voice along the way. Keep copywriting books of the great copywriters on hand and explore their techniques. This is what has helped me.
Cheers and have a great day Tom :)