I often use multiple types and sizes of needles in a single project -- often in a single day, so this is a big issue for me.
Even if I know the needle type, I have difficulties reading the size stamped on the needle. I cannot even read those with a magnifying glass. Maybe it would make it easier to see if I marked the number with a black sharpie, and then wiped off it off the surface. That's something I'll have to try.