PBR lighting; Transmissiveness; 3D model improvements & more.
I'm not sure I understand, the effects sdk already supports custom shader parameters. If we get access to the normals and lights we could implement custom (fragment) lighting already with direct-3d-rendering? (some helper functions like you added to wgsl would be awesome too for some common calcs like attenuation etc.)
Currently 3D lighting is a built-in feature of the renderer. It is not done using effects, because those run through the effect compositor, which is primarily designed to handle a sequence of 2D effects and has a relatively high performance overhead. So in my view using the effects system as a means to achieve this is something of a hack - it's just that it's currently the main way third-party developers can write custom shaders, but that does not mean it's a well-designed system to handle this.