I seem to remember them saying 10 was going to be the last one, too

To me the credit thing is less about "oh they made it so they deserve the credit", and more about spreading word about the free software movement. Software freedom is good, and GNU is all about software freedom, but people won't find that by searching for "Linux"

I had some past experience with Blender, but for functional designs I picked up OpenSCAD

Not unless I notice it printing poorly

Maybe if your printer is perfectly tuned and never has any issues. I don't have that luck with mine

I currently have mine almost on the floor and it's a terrible idea for ergonomics