To easily get a clear overview of the Digital Twins hierarchy of spaces, it would be great to add a (readonly) graph viewer for Digital Twins. A graph viewer has already been build and published to GitHub. Why not add this option to the Azure portal as the Digital Twins Explorer. (https://github.com/Azure/azure-digital-twins-graph-viewer)
Optionaly the explorer could be used to add, modify of delete spaces, devices or sensors in a non-readonly mode.