If you haven't already read How to Win Friends and Influence People, you definitely should.
I find that the children respond far better if I use their names when talking with them - but this is short snippets of talk (maybe 30s) with longer (20+min) gaps between. I always introduce my self by given-name and am surprised by how many of them remember me months later.
Partly I use their names as an attempt to remember them, partly to ease any discomfort or reluctance they have communicating with me and partly because I find it awkward starting a conversation or getting someone's attention without using their name.
For example, he points out that most people never accept blame for anything. From CEOs to convicts, we generally blame our failures on circumstances or other people. So with this in mind, he gives ways of steering people away from errors without raising their self-defense mechanisms or forcing them to admit that they're wrong. After all, do you want to defeat and humiliate them, or do you want to help them?
Indeed, the reason I liked the book was that generally, it DIDN'T seem fake. It encourages you to genuinely care about people. And says that, as it happens, this actually works better, too.
My view is hacking your personality is no different then improving your coding skills. It is just another skill set and there are advantages that can be derived from improving it. And, as you point out, personality isn't something that can be directly changed.. Thats called 'faking it'. No, personality means changing deeper things, like learning to care for people (or learning to care for yourself). Plus... Compared to coding it is a skill set that is far more useful and influential (unless you get really lucky...)