Fontastic is another solid option for that which enables us to choose items from multiple icon sets. The chosen items are combined into a single font with a click where this approach helps minimizing the font size as we only choose the icons needed.
It can group multiple elements which is useful when transforming them together.
There is a built-in animation loop,В methods to draw well-known shapes and lots of options to customize them.
There are built-in methods for creating shapes (rectangle, circle, polygon, etc.) or defining images.
It has support for grouping elements for mass manipulations, filling them is possible and a unified API simplifies working withВ theВ library.
SVG.js is extendable with plugins and there are already various plugins (like dragging or easing).