This is a very interesting concept. I've been experimenting lately with my own desires. I had to let go of a person, something that is normally very disruptive for me. But I recognize that desire is, as you said, a firing of neurons, which I conceptualize as energy. So I made the conscious decision to close my chakras and disconnect the energy. It's taken some mental discipline, but I've accomplished it. Of course, being in connection with someone is more enjoyable than being disconnected, but it was in honor of the other person's wishes and I found a way to reroute the desires without turning my life upside down. As I said, this has been an experiment, one I'm still learning the results of. I hadn't thought before though about using these abilities to control other people's desires. I do believe that PTSD, as you mentioned, can be healed through energy work. And there are practices for healing it in which therapists use semi-hypnotic techniques to recondition the thought process while the eyes engage in rapid movement. I think all of those uses are fine as long as the client is informed about the treatment and consents to it.

To answer your question - if I could change my desires... I would definitely use the skill to not desire relationships with people who are clearly incapable of being in them with me, be it friendships or any other kind of relationships... to alleviate the hurt that comes with endings... What I would desire instead... maybe to have stronger desires for spending more time (so I don't get busy & forget) with some of the people who want and/or need that from me.