I would recommend
The Elements of Moral Philosphy by James Rachels. It is a fairly quick read and clearly explains the short comings of most(maybe all) moral and ethical systems. It certainly can broaden your personal perspective on how people think and how your personal beliefs compare to the rest of society.
https://www.semanticscholar.org/pape...8d75950c18bc7b
I haven't tried the download, I hope it works.
A pet pieve of mine, people who think agnostics or athiests have less dedication, less morals, less ethics than religious people.
In fact, I have frequently found that to be the opposite.