I think you'd have to say that Works of Love is more in the "religious" category. It pretty much resolves that "either/or" question, at least to my satisfaction. The choices presented are not really "equal," since to love is a "commandment."
You do have to have some sort of susceptibility to the "religious" to take to heart the main text that Kierkegaard explores in Works of Love:
You shall love ...I can't think of book I'd more willingly recommend to anyone confronting the dilemmas of life. "Popular" books of the self-help, life-counseling genre make clear that "love" is not a matter of aesthetics. That is certainly consistent with what Kierkegaard says. My interpretation is that Kierkegaard finds that love is not really an "ethical" category, either. More of a secret key to happiness and success.