Any of the smaller items you listed would be fine, as would a bib or a changing pad. Personally, I've found changing pads to be quite popular with the grandparents. Just be sure to make it larger than you'd think & to pre-wash the fabric in hot water & medium-high heat. People of that generation are used to the days when heat was the only means to kill germs & get stuff "clean". I've seen those shrink by as much as 25% due to the way they're laundered.