Let's see what sort of "conversational counsels" -- principles directed to the removal of things that hinder the act of charity in the context of conversation, and yet are not contrary to charity -- might be generated from the evangelical counsels of poverty, chastity, and obedience.
Though there are already plenty of poor conversationalists, here a spirit of poverty would prevent someone from claiming ownership of a conversation. He might also refrain from insisting on any particular standing in the conversation, or on claiming authority others don't readily grant him.
From chastity, I'd derive something like keeping custody of one's tongue, avoiding topics and comments that, though not sinful in themselves, might tend to direct attention away from the path of increasing charity. "For the witchery of paltry things obscures what is right."
An obedient conversationalist might regard himself as the servant of those with whom he is speaking, or at least of the conversation they are having. The discussion is an opportunity for service, not for self-advancement nor for forcing one's own position on others.
As with the evangelical counsels themselves, all these proposed counsels as they might be fleshed out would need to be applied, not as rules to be followed to the letter, but through the virtue of prudence.