I quite enjoy your more cartoony style and I would honestly be kind of sad if you went more realistic with it lol, but it seemed like the area you could improve most easily with some effort.

Don't get me wrong I love the light use of shading but more on your more heavily shaded artwork, I think the best way to put it would be no distinct light source.
The shadows don't quite match or some prominent areas are missing shadow while others are well shaded.

I love all your stuff but if you want constructive criticism you could probably work on your shading a bit more. What shading I have seen you do has been kind of sparse and can end up looking a bit odd.
I love your drawings even unshaded though so that would probably just be pure improvement