So what conversational goals are consistent with the Christian vocation to love?
In trying to formulate an answer stricter than that given by general etiquette, I kept coming up with objections I could only answer along lines like, "True, this isn't a sin per se, but not doing it is objectively better." Then I realized my replies were expressed in much the same terms used to describe the evangelical counsels, which are a matter not of precept (which all are bound to follow) but of supererogation (which none is bound to follow, except to keep a vow).
Primarily and essentially the perfection of the Christian life consists in charity, principally as to the love of God, secondarily as to the love of our neighbor, both of which are the matter of the chief commandments of the Divine law.... Secondarily and instrumentally, however, perfection consists in the observance of the counsels, all of which, like the commandments, are directed to charity; yet not in the same way.
Then he draws an interesting distinction between precepts and counsels:
For the commandments, other than the precepts of charity, are directed to the removal of things contrary to charity, with which, namely, charity is incompatible, whereas the counsels are directed to the removal of things that hinder the act of charity, and yet are not contrary to charity, such as marriage, the occupation of worldly business, and so forth.
On the question of conversational goals, then, we might say there are precepts to which all Christians are bound, precepts against acting without charity toward those you are conversing with. These precepts would look very much like etiquette guidelines, though probably stricter than most.
In addition to these precepts, we might propose conversational counsels "directed to the removal of things that hinder the act of charity, and yet are not contrary to charity." What might such counsels look like? Maybe like the evangelical counsels...