Hi @mawa and @PatrickRyan, this is super helpful. I failed to mention this, but my scene is completely dynamic, both walls and furniture can be moved, time of day lighting is also in the backlog. My app is basically a canvas-based floor plan editor with a “live” 3D render. Based on this I understand baking lights / shadows / AO map is not possible at all, not even for the environment. Is that right?
From what I understand, this leaves me with the SSAO option. I currently have adaptive shadow handling for WebGL1 vs 2, Safari (zzz), and to get passed PCF breaking on some Android builds. I’d be ok with adding SSAO for selected hardware specs to gracefully adapt the experience. Also note that my scenes are quite small and low poly so I might be able to get bearable SSAO cost. I understand SSAO2 is WebGL2 only, but SSAO(1) would be supported by WebGL1 right?
I also will try a low hemi light and soft shadows as suggested by @mawa 
and maybe some ambient lighting from a skybox texture (would that help?).
Is it all a light and shadow game in your opinion or can I get closer through fine-tuning materials as well?
I’m planning to look at how they manage to get such nice material / light at https://gltf.pmnd.rs (try Suzanne). It’s using the Stage component from GitHub - pmndrs/drei: 🌭 useful helpers for react-three-fiber. I’ll dig into the code there at some point, and report back here if I understand something new. (Edit: At first sight, it seems the environment is playing a key role.)
Thanks a lot for the help, I have a lot to learn once I get passed the geometry side of things and I appreciate having this forum to turn to 
.