They're all very nice! Something I'd suggest is adding more variation to the line weight. A slightly thicker line which widens and tapers at points brings so much more life to a drawing. It also helps mask slight uncertainties in shape. Hair-thin lines like these demand perfection in a lot of other areas, such as shape language and anatomy, otherwise the drawing can come off as wonky/stiff.
Also, going by the sketch, if you're not practising figure studies, you should definitely do that. It'll help make your figures and your shape language more organic. 
There are no problems at all with the style! You should work in the style which brings you the most joy. If that's anime, you go for it!