- Multiple chart types (preferably also 3D charts)
- Charts should be interactive
- Animated graphics
- License that permits commercial use
Bonzai seems to be a good one. It allows for some pretty nice looking 3D charts (as well as interactive), the documentation seems to be quite good, and it even features an editor online. I can't talk as to how easy it is to use, as I haven't gotten the chance to use it, but from what i've seen, it's quite simple.
D3 is probably the biggest charting library for JS. It features a lot of variations for charts (a rough count in the Gallery is well over 100). It does have a bit of a learning curve, and all the images are dealt with in SVG format.
Finally, Rickshaw is a charting library that tries to simplify D3, at the cost of features (instead of 100 charts, it's at about 10).
Hopefully one of these work out for you! Let me know if they do, and if not, I could probably find more.
Supports multiple chart types including 3D
Supports interaction using events and also built in zooming, panning and interactive cursors
The SVG rendering mode supports animations
The community license is free and allows for use in commercial applications.
Note: I work for Syncfusion.
Note: the question here is clearly about Charts, like the libraries (charting engines) mentioned in the Comparison of charting modules, not to be confused with Graphs, as mentioned in the Graphing modules. Even though both links are related to drupal "modules" (which are like plugins), these linked page contains lots of links to 'libraries' (engines for charting or graphing).
PS: the question contains "... a better chart library ...", consider editing your question a bit to explain why that word is included, i.e. what kind of issue are you facing with the current library that you'd want to be addressed.
RGraph can be used under the GPL:
The latest release adds integration with Google Sheets.
PS I make it FYI
LightningChart JS allows building charting dashboards with WebGL acceleration, and might be an overkill solution for your needs, eventually? It's super-fast, and low-cost, and free for personal use. For commercial use we ask small fee.