Various embodiments relate generally to electrodynamic machines and the like, and more particularly, to rotor assemblies and rotor-stator structures for electrodynamic machines, including, but not limited to, outer rotor assemblies and/or inner rotor assemblies with a corresponding stator assembly. In some embodiments a rotor assembly can include magnetically permeable structures having confronting surfaces oriented at an angle to the axis of rotation. A group of magnetic structures can be interleaved with the magnetically permeable structures. The magnetically permeable structures can also include non-confronting surfaces adjacent to which boost magnets are disposed to enhance flux in a flux path passing through magnetic structures that are interleaved with magnetically permeable structures. Further, the rotor assemblies can include a flux conductor shield disposed adjacent to the boost magnets, the flux conductor shield configured to provide return flux paths.