I think the 3d printer should allow you to scan and print uncraftable blocks. For example: horizontal and vertical sewer pipes, metal bars, pile of books, copper platform etc. It may also be helpful to be able to scan some blocks which can be crafted, like unrefined wood and platforms so you can buy them with pixels if you're too lazy to go out and chop trees.
Absolutely. If it cannot be crafted but can be obtained through exploration, they should let you scan it.
Yeah, absolutely. That's what the 3D printer is for, printing things you can't craft. It should live up to that purpose!
I like the first part (being able to scan uncraftable blocks) - It gets old that I run out of a block I am using, only to fly around planet to planet to find just that 1-2 last pieces I need... I love some of the block designs, but I would love to be able to craft everything I see in some shape or form.