learning new chords and practising switching smoothly was the biggest frustration in my first few months of guitar playing. And when i mastered that, learning to curl my fingers and play one finger per fret was was the next frustration for the next few months. After that was learning to hold my pick properly, which i still can't up to today. That's one of the reasons why i switched to bass. Which brings a whole bunch of frustration again.
But the thing i found out is, if you have interest, you learn 10 times faster and you will be 10 times more patient and 10 times more disciplined. So you're learning and practising how to be patient and disciplined all at the same time. Which is cool.
So irrelevance aside, i think chord changing is something very basic and cannot really be mastered. In a sense that if you are switching between these complex chords like those maj dim sus add blablabla chords (can't think of any examples, it's 6 am now

). But i guess nobody really needs to switch between such complex chords anyway. But just bear in mind, that it is a continuous learning process. For me anyway.... Oh and when practising pluck the strings separately while holding down the chord. Each string should give a clear buzz free tone. Try not to squeeze the neck too hard until your finger tips all become white. Accuracy is often neglected and replaced by brute strength. Which works most of the time, but....well it's a bad habit i would say. Have fun!