Hard for me to get behind this app when it makes my handwriting terribly shaky. Could use a stroke smoothing feature, like you would find in art apps, to help pen strokes looks less wobbly and therefore look more like our handwriting.
Also a Pressure curve would be great. I had to hold the apple pencil incredibly lightly in order to get the thinner stroke from the brush pen; it goes to its maximum selected width way too quick, which defeats the entire point of choosing a brush pen over a felt pen.