After some tips on shapes and styles I tried keeping his features but change his style:
I think it started to clear up at around number 3 and my favourite is number 5, a more cartoony version of the famous dragon:
Then I was given Buttercup and changed her shape but tried keeping the main things that make her character.
Anyway it was really fun and it is really nice to hear some basics on character design, definitely helpful. :)