One more for the collection and yes, coloring this one also involved a lot of guessing.  
Since Professor What is clearly based on Roger Delgado’s Master and is also described as Doctor Hooves’ evil counterpart, I took some cues from them to use as What’s colors. (I also loved how Doctor Hooves here has some of the Third Doctor’s sass.)
 
Having said that, I would really appreciate if some day the Manga crew released some colored pics to know for once and all how some characters and objects are supposed to look.