I’ve found in this post that a good amount of people tend to imagine the presented characters based on their “feelings” instead of the given descriptions.
Even when the descriptions are clear some people make their own image of the character based on how they feel, or I guess, past real experiences, either in real life or comparing them to another fictional characters they found have similar personality traits.
Many others just forget the descriptions unless it’s brought up recurrently.
I guess that for a visual representation it’s kind of hard to care when you never get to experience it visually. The readers only see black and white letters on the screen (unless you add drawings). Most of them don’t have a memorized list of traits to remember for each character, they do so by feelings, on how their minds react to the actions the characters do.
An example it occurs to me will be:
The girl came up dragging one of her foot with effort, wincing every time it stomped the floor. Blood streaks running down her cheek. She snore through her nose and spit out streaking the pavement with a red blob. Her eyes go from there to the baseball bat on her hands, this one dripping even more red liquid than her, of course the other one ended up worse…
There you have a very short introduction without descriptions. I wouldn’t be surprised to find most of the people would make a mental image of that character as a badass girl, maybe with half her skull shaved, red hair, tattoos, (add whatever cliche trait of known badasses girls they know of)
On the other hand, some people likes to be given all the details, and you have the tools to do it. Does that means your book will be better if you do it? I don’t think so, but it could add a point in favor. Only you have to determine if it’s worth the effort.