This is great! The example page on official d3 is a bit dated and certainly has "grown" over time. I also particular don't like that d3 is too much of a "one tool for everything" approach. I.e. the data calculations and the drawings shouldn't be done in the same framework (thats were React comes into play).

My biggest pet peeve with D3 is the lack of TypeScript friendly-ness. I not only mean the lack of official typescript .d.ts bindings, but the API itself is completely not designed for strict typing. Functions are heavily overloaded/polymorphic, take all sort of different types of parameter shapes, and change their return values on what is passed in etc. My experience was always, once I got my code "properly" typed, the next update of the .d.ts bindings would break again, and this would repeat every couple of weeks.