There is an interesting abnormally with the 0.5mm x 0.5mm matrix in so far as the dot size is smaller than I can cut a hole in a piece of kapton. It would appear that as the center of the beam contains more energy if you fire it quick enough you can get a smaller dot size. Strange.
No, that is normal for a stock laser beam. It's called a Gaussian distribution. Commercial laser-cutting machines often have some expensive beam-shaping optics to convert that into a flat-topped distribution, which makes for better cutting in heavy metal at a commercial scale.