"Your hair is a really nice shade of red, its really cool" is a better way to say it than "your hair is a beautiful colour" the second comes off full on and might be too much. Generally, with compliments, saying less is actually more.
Stop encouraging him to harrass women while they're working. When I worked in a bar I had countless numbers passed over the bar to me because they thought it was appropriate and I threw out every single one of them. People don't want to have to deal with being approached while they are working. Or after work, if its to do with their work place. Meeting somebody in their place of work isn't appropriate and isn't how to start a relationship with them. Its not a club.