Receiving shadows on Emissive Materials

I am working on a shader of sorts which uses material parameters, but it uses mostly Emissive properties due to lit shading not giving the look that I want.

I am wondering if there is any way that I can get self-shadowing and shadows based on the level lighting to work with Emissive materials without having to switch to a dodgy post-process solution entirely, or without having to spend large sums of time figuring out how make a shader model which uses emissive but accepts shadows

Well, Shadow is absence of light. So it is mutually exclusive with emissive. You could try achieving the same effect with a bright basecolor. If that is not enough, you will need to alter the shading model itself.