Rayin,
I would not be kicking myself (unless you are flying every week). If you invested that $500,000 at say 6%, you would get back $30,000/year. YOu can do a ton of flying for $30,000/year, I have got to believe more than what you could possibly do. And that was a coach number if I remember right.
You did ok. Now had you passed on lifetime club cards you may have true second thoughts.
FF