you could work on shading more

YES

...Good enough for who??? My advice: Don't worry about what other people think, just enjoy drawing for fun. (but I'm super bad at following that advice...lol) But hey, maybe you just wanted constructive criticism. If so disregard ^^ XD I guess I would say if you could make your lines smoother? If you use a larger size it's usually easier. Don't take my word for it though, just do what you want to do. :)