When you are writing a story and refer to a character by a physical trait, occupation, age, or any other attribute, rather than that character’s name, you are bringing the reader’s attention to that particular attribute. That can be used quite effectively to help your reader to focus on key details with just a few words. However, if the fact that the character is “the blond,” the magician,” “the older woman,” etc. is not relevant to that moment in the story, this will only distract the reader from the purpose of the scene.
If your only reason for referring to a character this way is to avoid using his or her name or a pronoun too much, don’t do it. You’re fixing a problem that actually isn’t one. Just go ahead and use the name or pronoun again. It’ll be good.
This is very true. Unfortunately I did do this when I was writing my first novel (I’d been doing it for a long time in fanfics as well), thinking I needed some other epithets to call charactes instead of just their name, and it’s the only thing that I’ve consistently gotten negative feedback about. At first I thought it was just my niece, but when quite a few other people pointed it out as well I figured they were probably on to something. So now I’m trying to avoid it as much as possible.