There are several excellent mount methods shown in the FAQ.
wiki.arcadecontrols.com/index.php/FAQ#Joysticks"Under mount (support blocks)" is a very popular method to solidly mount the stick to the panel without having to worry about structural support if the pocket you route for the stick is fairly deep.
If you use MDF for the panel, the threaded inserts ensure you can remove/repair/reinstall the joystick repeatedly without stripping out the screw holes.
The easiest way to do this mount is with two bars.
You can use metal spacers like Gilrock did for his ServoStik mount
here.
If I use a 3mm hardboard and a 1/2mm of plexiglass on top, is 4/5mm a good thickness in your opinion?
1/2mm plexi sounds
way too thin and likely to crack.
Some people don't like plexi because the smooth surface traps sweat when you rest your hand on the panel.
One way to avoid these problems is to buy artwork printed on vinyl and laminated with textured polycarbonate.
- The lamination is thinner than the plexi and it is flexible so you protect the artwork without having to worry about the protective layer cracking.
Even if you use several thin layers on top, you'll still need a thick layer underneath to provide structural support for the joystick.
You may want to consider eliminating the thin layers.
- Route pockets for the Sanwa buttons (OBSN 30mm screw-type?) and joystick in the thick layer (usually MDF or plywood) and prep/prime/paint the top so the art adheres properly.
- Use vinyl artwork with textured polycarb lamination on top of the thick layer.
Scott