We actually use 2 density standards:

1:    Extra light: 40%, Light: 60%, Medium light: 80%, Medium: 100%, Medium heavy: 120%, Heavy: 140%

2:   Extra light: 50%, Light: 80%, Medium light: 100%, Medium: 130%, Medium heavy: 150%, Heavy: 180%

1. 100% medium=2. 130% medium

With too thick hair it doesn't look natural. And it's impossible to make a natural parting. It will be too tight - a real wiggy look.

Light to medium should be good enough for most men.   And medium to med heavy for women.

If you are a little bit wiser (older) don't go for too much hair. And choose a lighter color. And let it be possible to see your scalp a little bit.