Does your protagonist have any imperfections?
I am not a perfect human being. I have a flattened spot at the back of my skull, no nose cartilage, and both my little fingers are a weird shape. If I was to start listing my personality flaws, we’d be here all day. And yet, I’m an attractive woman with a pleasant personality. My flaws just make me … me. There a millions of pleasant, attractive people on the planet, but my imperfections assist in creating my individuality.
The same should apply to your protagonists and antagonists and every other character in your narratives. A truly perfect protagonist lacks realism, and your audience will find it difficult to relate to them. A too perfect protagonist runs the risk of becoming a Mary Sue or a Marty Stu. Or worse, boring.
Don’t fall into the misconception of making their virtues seem like faults, because your audience are too intelligent to fall for that. It’s a bit like being in a job interview, when they ask you ‘What’s your greatest problem’ and you say something like ‘I can get too obsessed with getting everything right.’ Everyone around the table knows that you are not going to admit to having homocidal thoughts about any workmate who interrupts you while you are on lunch. But your readers should know that kind of detail about your characters!
I am currently updating my character profiles for my train book, now that I am nearly half way through the narrative. My characters have evolved and I want to keep their folders relevant. I just noticed that I haven’t really described how my main character looks in the text. Time to polish those flaws.