I'd suggest you use a JS library like HighCharts or D3JS (or both). All you need to do is format your JSON on the back-end in the correct format and throw it into the chart's configuration.
HighCharts has an amazing API, documentation, and examples.
HighCharts has an amazing API, documentation, and examples.
In other words, is it like Bootstrap in that it's a useful starting tool, but doesn't really scale well if you want to have full design control in the longrun? Do you happen to know any notable sites using Highcharts? Thanks in advance.
The API docs are just fabulous, with examples for everything :)