This is my example setup. The idea is to have mask of things grouped and named for better usage and readability. Like not mixing product related mask with prop related. I end using at almost 100% of the time Product 001 and Decor 001 other parts are if need or just in case.
Name: Product 001
Type: MultiMatteElement
Info:
Red: First Product Colour (mat ID 1)
Green: Second Product Colour (mat ID 2)
Blue: Handles / Third Product Colour (mat ID 3)
Preferably Setted by Material ID
Name: Product 002
Type: MultiMatteElement
Info:
Red: Worktops (mat ID 4)
Green: Alt Worktop (mat ID 5)
Blue: Additional Product elements (like wood, internals etc) (mat ID 6)
Preferably Setted by Material ID, this is more relaxed not strict.
Name: Decor 001
Type: MultiMatteElement
Info:
Red: Ceiling (mat ID 7)
Green: Wall (mat ID 8)
Blue: Floor (mat ID 9)
Preferably Setted by Material ID
Name: Decor 002
Type: MultiMatteElement
Info:
Red: Additional Floor, Wall (mat ID 10)
Green: Woods, beams (mat ID 11)
Blue: Curtains, Blinds (mat ID 12)
Preferably Setted by Material ID, this is more relaxed not strict.
Name: VrayReflection
Type: VrayReflection
Info:
For Adding/Removing reflections
Name: VrayAlpha
Type: VrayAlpha
Info:
Just to have Alpha Mask
Name: VreyExtraTex
Type: VreyExtraTex
Info:
Almost every-time will need this when we have painted grain or something similar.
Also try making Fusion files more organised:
Red: Align Pre-setted mask and passes with the main loader so everyone knows that this must be reloaded again with the new render
Green: When using and reusing one pass try to use only one loader (saves memory and you need to change single loader)
Blue: Use inflow connections for passes/mask manually rendered