Some of the things I learned from David McKee were these:
* That it's okay with play with perspective and pattern. I think looking at Dave's work was what first made me step out of trying to be somewhat photographic in my perspective, or at least use traditional European perspectives. I suspect he learned a lot from Indian art, I see a lot of traces of it in his work. Although it could also have been a sort of mashup of English folk art and the vivid 1960's patterns.
* That you don't have to follow the herd. David McKee's politics didn't always match up with what was considered laudable and acceptable in book world. I'm not saying he was right or wrong, just that he didn't agree with people just to stay popular, he thought for himself. And when he was fed up or just fancied something different, he quit and went and did something else, painting big abstract canvases instead of children's books and animations.
* He worked right into old age, and his work just got better and better instead of getting into a rut. This is always inspiring.
* He was a gentleman and utterly charming. Kindness and politeness can go hand in hand with fame and a busy schedule.