I find that if I parse my "negative point of view" in the form of a question, there's less chance of offending, and more opportunities for the other person to paint themselves into a corner.
"Can you explain why a Muslim woman is expected to cover herself? I don't understand this."
"I don't understand why Allah permits a man to have many wives, can you explain that?"
"I don't understand why someone like me is considered an infidel, just because I believe differently than you. How does that work, exactly?"