This is really great and I would not know where to start building this. The only thing that I would like to have is the use of "modern" JS tech like ES6 and a build pipeline... Surely this can be added later as well.
There are some features in ES6 that could improve the coding but nothing that is really game changer for performance, but ES7 will have SIMD support, that would be amazing
In a project I worked on I used SVGs from the designer and animated them with Javascript (Velocity.js in this case). The trick here is to inline the SVG into the HTML page (can be done with a preprocessor). Then the SVG DOM nodes can be animated as you like.