Yeah, if you’re using Lumen you can only use movable lights. They’re not great on performance, but Lumen does help to mitigate the cost in comparison to traditional rendering. There are a lot of optimizations you can make for lights and Lumen, but I really wouldn’t worry about it too much if its not hurting performance. If you want a full breakdown on optimizing Lumen lighting, you can take a look at my response here:
I do think that’s a common sentiment haha. There is always more to optimize, and that’s why it’s really important to start optimizing during your production pipeline, and to know where to focus your time.
This page is actually a great guide on how and when to optimize:
Well, less of an atlas and more of a trim sheet since the goal is to only use one material and one UV set. Let’s say you have a house material that has 4 material slots- 1 for wood, 1 for metal, 1 for glass, and 1 for wallpaper. You’re better off combining the materials for wood, metal, and wallpaper and just baking the textures in Substance Painter. The glass would need to stay a separate material slot since glass is a completely different material type and not reliant on textures.