Nice breakdown, and I'm sure it will help some people who have no idea what a lighting system consists of, but it doesn't go into any detail on the polygon clipping algorithm (which is the heart of your system). Clearly you are trying to help people... Why not provide source code or a detailed explanation of the algorithm? Otherwise I don't really see the point of your videos.
I like your system, though. Mind you: there's no need to bind/sample a texture. The radial fade out and colouring can be done in a shader, probably more efficiently.
For soft shadows, you could apply a full-screen blur shader
of your shadow maps at once. Depending on your scenario, it may be much faster than blurring each shadow map individually. For added effect, you could increase the blur size based on the distance from the light center. The result will look very good, probably identical to my own lighting tests
, the only difference is that yours requires much less overdraw.