That's a lot of sketches! And here I was thinking of just winging it.
Still plan to wing it xD, since my current focus is elsewhere, but I'll at least join you guys from the sides.
On the pose and anatomy side, I usually look for a pose I like, extract the gesture, and reconstruct it with a basic human shape as I keep an eye on the reference for some of the fine details like hands. Sometimes I'll even combine gestures or different references. For example, I'll frequently take photos of my own hands on the exact angle I need and use that as a reference.
I used to try to do more from imagination, but quickly learned I need to use more references for now, until I have a better mental library.
I think you already know all this so probably not much help.
If I'm REALLY struggling, I might go as far as trace a few main features (just few main lines, I try to keep that to a minimum), then remove the reference and continue building the shapes around it. For the most part I'm trying to "extract" into my memory how the body works.
I've found flipping also helps find glaring disproportions.
In your example here, it looks good for the most part, though her hip seems a bit rotated more upwards towards the camera while her leg comes down a bit more, while yours seems like the hip is resting down more and the leg points up a bit. It's really only noticeable when putting them side to side. Probably not even worth mentioning.
Overall I feel the basic structure you have is fine, but I've found that the next step is to get muscles right, which adds that "organic" feel, and is SO much harder to do.
In this example, there's a slight indent where her leg connects to the buttocks. The leg under is squished and her muscles reflect that. The skin and muscle sin her torso twist which make the note more dramatic, and if you were to increase the bust size, it would need some work to get them to fall properly (or be pulled by the bra).
