Looks good to me so far ;-)

First criticism I expect is for many to insist on a class-style vector
library, which I personally think has no place as a low level, portable API.
Everyone has a different idea of what the perfect vector lib should look
like, and it tends to change significantly with respect to its application.

I think it would be useful, especially to newcomers who are unfamiliar with D's lib terrain, to have an officially supported "utils" library for these higher-level structures.

core // to the metal
std // low-level but useful
util // get the job done