I get your meaning, but the issue is really about quality fidelity between the character authoring tools and Unity. I have AAA character design models with high micro normals for skin, etc. The problem is that, hours and hours of tweaking in unity with Shadows, Light, probes, SSS, etc only get you about 40% of the way in terms of fidelity with HDRP, even if you use custom skin shaders, hair, eye, etc.
The workflow pipelines can be pretty complex, especially if you have a model that needs to express facial emotions (blendshapes or meshmorphs) and speak with synchronized audio. Some of these character design tools have exports, specifically for Unity HDRP, but they still produce a less than ideal Unity model for closeups with cutscenes. They’re great for if the camera is 10-15 meters away, but for cutscenes, you need to have the camera close. When that happens, the character details for skin, eyes, and hair are not very good due to how HDRP is rendering the models, even with high subdivision and 4k textures.
I’m not trying to diss your posts on advice, but I’ve already done all the things you have suggested. Normals, multilayer texturing, HDRI’s, 3 light studio configurations, shadow tweaking, etc. This is not so say that I haven’t had a “okay” result with these things, but it’s still a bit of a boondoggle to get a much higher quality result with Unity HDRP.
Update:
Recently, Unity posted information on a new tool called Lookdev studio, in that, they recently showed a fairly decent character model in Unity. LookDev Studio Unfortunately, they don’t talk about the workflow for that particular model, who designed it, what software they used, what the pipeline workflow was for import, etc. I’ve asked if they can share more info since it looks about on par with the digital human package, but I’m guessing it isnt the DH.