Absolutely! They are lighter than the 3/4 boards, I had to exchange them out for the heavier/ thicker ones on my gate because the other ones were too heavy. They worked great !!
Yes, we just did that replacing the heavier ones (3/4") on our gate- they are lighter and worked great !
Yes, but it depends on what you mean by "cut the boards down" which determines how much they will do it for. Home Depot has the equipment to cut just about any "board" any way you like. Great service!
With the proper sanding and finish, it might be quite nice. However it is a soft wood and would likely scratch easily.
It was just plain old pine