I really like
Grace. It is on my favorites list. I don't think of it as overly religious. I think of it as classic, sweet, vibrant name.
I think it is kind of common. It is classic though and any
Grace's I have known have been really spread out in age. So I don't think of it as super popular or common that your child will one of 10 in a class (although maybe in same communities or social circles).
I don't mind it as a given name but try to avoid it with a really common first name.
I also am not a fan of
Gracie. I don't mind it so much as a nickname but really dislike it as a given name.