For the particular style, you'd need stronger colors, more contrast, larger eyes, larger hands, feet and a pose that isn't as strict and straight.
Basically the body of your sprites is like a shampoo bottle.
You need to draw with more flow and motion and not restrict yourself to straight shapes.
Also, animation wise, a walk relies heavily on the thighs, while your guy seems to be controlled by the lower part of the leg.
The thighs should carry the lower leg, because you basically can't move the lower leg forward without moving the thigh.
You have an entire sheet of sprites you can use as reference.
(although, those sprites are much higher resolution)