I have learned that a Mesh with 4 Materials each 1024x1024 in Size is somewhat slower than a Mesh with 1 Material 2048x2048 in Size? In my usual workflow I tend to seperate different Materials into different Materials so an Object tends to have around 2-8 Materials. I have created more than a hundred Assets like this.
Is the performance dramatically affected by this? Is it acceptable to upload such Objects to sites like turbosquid or sell them on Unity Asset Store or will the buyer behead me after noticing?
Window Textures need to be transparent, Metal / Wood / Concrete need different smoothness settings. As far as I know Unity doesn't support Gloss maps.