I’m personally guilty of forgetting the other side of the “coder colours” thing (tip No 8): i.e. I will generally try to cap the RGB values at a reasonable high point…but I will often let a channel drop to zero. All out of laziness: to truly prevent this, you need to check your map’s darks. You’d think someone like me who edits at least 50% of all the maps in any given scene would bother… ha. Lazy Fox!
NB: it only applies to _colour_ maps. A control map like opacity strength or any other strength, now this should have a zero when there is no effect (or when it goes max distance into the surface, like bump/displacement). Same for max values: they are there when they are needed.
And the tip No 1… I swear it’s the key point. It did literally change my renders overnight, even before I moved on to custom shaders and full GI.