Well, I have a (not very creative) female torso. It's rather thin and simple, but its hip and shoulder joints are at the same height as those of Kopaka Master. It's also a bit wobbly around the waist area and has like no back armor (because of those blue half-pins for attaching weapons); but I do think that it can serve as some kind of inspiration or base to build around.
I would recommend putting some tires on the hip joints to fill out the gaps.
I could've edited this into my other post, but this is about a different thing, so yee
Ever wanted a really small Matoran build, around the same height as a Voyatoran, that uses way too many ball joints and Mata hands and also has hip articulation and a hunchback? Well, then this might be what you've been looking for:
This obviously is the version for heads that have a socket. And my least favorite because of the hunchback that's just fixed there. I'm sure someone (or even I) can come up with improvements.
It even looks like he has some spine bones:
Here's the version for heads with balljoints, let's call him Bulsik:
And here next to our favorite hunch-backed Matoran: /spoor Velika just wants a hug
I'd love to make more right now, but I don't have any parts left.
Edited for Double Post.