We are currently implementing new playground which will work more like codepen and we expect jsreport developers will create and share there many ready to be used templates. That should be live in the next weeks.
However I am afraid there is nothing you search for at this moment.
jsreport is for now targeting mainly developers.
There are tons of existing charting libraries or html/css templates ready to be applied in jsreport.
We keep it up to developers to find and apply lib/template they like.