@Geoffrey-Gordon You're quite welcome!
Yes, in general a good pose/character is when a person can glance at a page and quickly understand what the character is feeling/expressing. Think about how we read children's books. We flip the pages (sometimes quickly, sometimes slowly) and a child, especially if they are not reading yet, must gain quite a bit of knowledge from looking at the images on the page.
If a child cannot understand the feelings expressed by the characters, then they are missing out on a key part of the story telling.
It is good practice to draw silhouettes of your characters to learn to see if the pose is dynamic. I don't feel that it is necessary to always do so, but if you are learning it then I highly recommend starting off by doing that.
For example, sketch your character out a couple times in a couple different poses - then on a separate layer on top of that fill in the poses with solid black to see which pose reads fastest.
Another good exercise would be to make a list of expressions - perhaps start with 10. And try to only use silhouettes to create those expressions. Show them to another person (or on here) and have people try to guess what feeling the silhouettes are trying to convey - if people are able to understand your silhouettes move on to filling in the details. If people seem confused or unable to understand the expression, then it's back to the drawing board!
I do tend to ask myself a lot of questions before I start an illustration, but I don't necessarily have a list... It's sort of second nature at this point but it does take a lot of practice to get your brain to think about them without a lot of effort at first. Sometimes I'll write out a little story for the image, in that story I'll try to make sure to hit some key elements: what time of day is it, how is the character feeling, what is their goal?
All these things inform the illustration and therefor inform the character design as well. Is your character young, old? Are they a teenager? Are they in their 30s? What's their job? Do they like the color green? Or are they more of a purple person. The less generic you can think, the less generic your characters will feel.
Another fun practice is doing this - start with random blobs. Try not to think about what you're doing (this can be done digitally or traditionally with watercolor.) Make a bunch of blobs and then try to fill them in with unique faces. This will help break the tedium that many artists face because we are saturated with very similar images/styles these days. We are influenced by what we see and what are the trends. The goal is to break up our imagination a bit to stop relying on our "stock visuals" and therefor create unique, expressive, characters. This will also help push and pull the sizes of your characters features. You can do this exercise with whole figures too - just use the random blobs to contain your character. Sometimes restrictions are a key to unlocking creative solutions!
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