PFE should be able to create IK chains if it's not working via Poser's hierarchy editor.

I'm hoping it will help me solve any valueOp issues I might run into as well.

Orion has a Pelvis between the hip and thighs.

IKs seem to work just fine.

A thigh rig setup with an extra horizontal bone to simulate the femur neck wouldn't serve any true purpose that I can think of in a human figure but would instead cause more issues with weight maps. And probably IK. Rig bones aren't exactly the same as real bones. For that matter I've yet to understand why some figures have an extra twist bone whose only purpose is twisting.

At one point he had tarsals in his feet, but he also has heel bones, and I couldn't see any benefit to the tarsals other than interfering with proper foot scaling. They didn't make for any more realistic posing and would just be another hassle to deal with in rigging shoes, so they got removed.