To answer the questions, yes, I did model the 3D models myself in Maya, and you are free to download and print your own if you'd like.
I didn't do any sanding on them (they're pretty small, only 10 cm high) since I was afraid I'd just file off the details them, plus the 3D printer I'm using
(Creality 10s) is pretty good at fine details, though the downside is that even these small things take hours to print with those settings.
I'm not one for figurines but it might be cool to have one of my games' characters, or a ship.
If you have access to a 3D printer, I'd say go for it. For any AGSer who already make their graphics using 2D images of 3D characters,
you can just convert the 3D files to an OBJ or STL file, and as long as there aren't any gaps or holes in their geometry, they're ready to be printed!