If a family member is OTD, we need to express our disapproval and disappointment, but with a friend or acquaintance, we can be more open-minded and welcoming.
I have several acquaintances who are from the former Soviet Union, with very little contact with yiddishkeit before they came here. Anyway, I tell them that Judaism is something that is their birthright, and they should make it a part of their life. I encourage them to light Shabbos candles, and make Shabbos special. Restrictions and limitations can follow later.