A bit of an issue I have with your designs is that they don't clearly convey what the characters are supposed to be. I can tell that Dame Nic Bochra is some kind of warrior, but I know nothing about her aside from that. Her expressions, body language, and clothing/armor are too generic for me to glean any personality from her character.
The male character is much better since it's very apparent from his sharp-angled clothing that he's meant to be more villainous and sinister, or at least an antihero if not an outright villain. None of his designs are bad, but the best choice depends on what you're going for with the character. The top row designs imply a more rustic, itinerant character; the middle designs imply a more militant character, like a general or commander; and the bottom designs look more formal and imply that he's a noble or political figure. Again, go with whichever design best suits the character's personality and role.
You should also consider the silhouette when deciding on a design. The middle designs have much more distinct and recognizable silhouettes compared to the rest.
As for the art itself, you have a bit of a problem with proportions. A general rule of thumb is that the top of the head to the bottom of the crotch should be equal in length to the legs, similar to this Loomis drawing.
As you can see here, her legs are about half a head shorter than her upper body.
She's obviously meant to be a somewhat diminutive, thicc dwarfish character, so shorter than average legs makes sense, but her lopsided vertical proportions make her look awkward, especially considering her sexy, curvaceous appearance, which people usually associate with proportionally longer legs.
The male character looks better, but I still think his legs could stand to be a bit longer.
In general, longer legs look more aesthetic, and make characters appear more athletic and imposing (or sexy if the character is female). A lot of character designers and concept artists draw slightly longer legs for those reasons.
This character has a similar issue. Her thoracic section is way too long.
The pose on this drawing also looks a bit weird.
Since the axes of the shoulders and pelvis aren't parallel,
I assume you were going for a contrapposto pose, kind of like this.
But I think you misunderstood how body dynamics work. The weight-bearing foot should be vertically aligned with the body's center of gravity, which for women is approximately in the middle of the pelvis, around the location of the reproductive organs.
You seem to know what you're doing in this regard since you consistently align the foot with the pelvis.
The issue arises when we look at the overall body. If we draw a line through the centers of gravity, you'll see that the large majority of the bodies' mass is situated on one side.
These bodies aren't balanced. They'd likely fall over in real life.
A lot of artists like to simplify body dynamics and instead align the weight-bearing foot with the pit of the neck.
It's not completely accurate but usually looks fine, and typically avoids this imbalance problem by ensuring that the upper body is balanced.
If you weren't going for a contrapposto pose, then ignore my autistic tangent. Still, the pose on the right looks kind of awkward and could use a redraw.
The length of the legs also looks weird.
The difference in the lengths implies an extreme perspective angle, like this.
Notice how foreshortened the far legs are on these figures.
In your drawing, however, the feet are on pretty much the same level.
Those are the major problems I've noticed. Everything else is mostly just picking nits. There is a bit of wonk here and there though.
You generally have a very good grasp on anatomical perspective, something even a lot of experienced artists struggle with. This drawing is a bit of an outlier though.
Since we're looking down at her, her facial features should be aligned on a steep incline, similar to how her boobs are aligned.
You didn't make the same mistake on this drawing. This is really good.
And this girl's head should be skewed a bit to the left.
Sorry for ragging on your work so much. You really are a great artist, and I wouldn't be nitpicking so hard if your work wasn't as high quality as it is. I think if you improve on a few weak areas, your art would be next level.
If you don't mind my asking, what are these drawings for?