Watercolor paper can go bad. Sometimes oil paints can go bad. Daniel Smith watercolors are fairly good. I like their Primatek Gemstone watercolors.
A fountain pen called "Flow Fountain" with a ballpoint pen. Might be good for folks who wanna get into using fountain pens for sketching.
I'm getting posca markers for when I can't get up and do acrylic painting, of course. Some colored pencils.
Well. I'm trying to see what I actually need, you know.