>>2263873ive found the best way to capture likeness is 2 things. 1 get the shape of the head right. make it really obvious as a silhouette that it's you. 2 symbol draw the features. render everything else however you'd like but make sure you capture the symbols of the bottom and bridge of the nose, the shape of the eyes, eyebrows shape of the ears and the shape of the mouth.
I'd say the mouth looks pretty good, even if it looks a bit pasted on, but the nose and eyes have no personality. they look just as worked as the rest of the face which makes them blend into the rest of the painting. I'd say look at van gogh's portraits to get a better sense of this.
try to bring a quick confidence to the way you draw in the features of the person.