I think the detail on the muscles is to die for.

I would say that the overall proportions for this could use work. You made Kefla look way taller than she actually is in Dragon Ball Super and with said proportions her face looks a little bit too adultish with how far down the mouth is from the mouth and nose.

Badass art of the Strong Gal Kelfa here mate! really great shading and nice action pose as well. Nicely done here!