oomis- that approach is correct. one should, however, have in mind at the actual naming of the child that the name for someone not frum should not be referring to the grandparent but to some tzadekes with that name. “
Interesting that you mention this. We actually were mekavnim exactly that way when we named our daughter. Though she is named for a specific person, WHEN she was named I had in mind something connected to the meaning of her name,something spiritually significant to klal Yisroel, rather than the person for whom she was named.