Lighting shines too much on toon characters
Reduce the Specular Contribution setting in Radiant Artistic Controls section.
I get artifacts when using the Complex Lit shader in deferred (URP)
Select Radiant Render Feature and set it to deferred and render event to “After Rendering Deferred Lights”.
What's the Normals Quality option for, in built-in pipeline version?
Using high quality normals is always recommended. The “Approximated by Depth” option will provide a slightly faster result in exchange of quality, including lack of bump-map support (it can be useful for low-poly scenes for example).
Some objects are visible through terrain when using Radiant
This issue only occurs in forward rendering path when the terrain Draw Instanced is used due to the terrain shader lack of depth/normals pass in this mode. To solve this issue, switch your camera to deferred (deferred is always recommended) or use the “Approximated By Depth” normals quality option in the Radiant camera script.