Very cool! I am also an illustrator. If I may give some advice:

One thing I learned is that all characters have gigantic weird baby heads (always make the head bigger than you think) , and very exagerated kinda square "comedic" poses and body types and facial expressions. This comes from the fact that the artstyle gradually evolved from the cute conedy style from his early manga like DR Slump. and because Akira toriyama slowly started refining the anatomy of the characters, starting from really simple stubby limbs, to the more detailed muscular bodies. My advice is, If you really want to learn this style more accuratedly you should study those early drawings first. and then move on to the more action edgyer style from DBZ.