Hi Dak_Lak, thanks for your insights.
This acrylic plate is made by laser cutting, and could choose the thicker plate like 3mm/5mm to make it stronger. For Grove modules and main board, it will give well supports, for display and prototype purposes.
Here I attach my draft design Grove Plate CAD Design .dxf file
for you, in case you would like to modify it to fit your specific purpose.