You forget "retina triangles" or how-they-are-named.... Also i recomend using ctrl+shift+с on hard edges to soften 'em. (like lines on her tail and mane somewhere look "broken", not soft... if it's intentional, than ok)
It also is very useful for me to make lines into spase with ctrl+alt+с so u can adjust edges precisely.
I don't know which tut u used, so i brought up key-combos, which i found very useful...
Thank you for feedback and key-combos... but really this vector was made in first day of using Inkscape (then fixed) here you can see the difference (and improvement) in my technique in speed drawing video and in this vector [link]