Friendly speaking, we didn't make a performance or optimization research yet. I can only share an experience we've got from using taucharts in our main product - "Targetprocess".
So we setup a limit to 1000 rows (+/-50%) which seems to be acceptable performance / usefulness balance to draw a chart within a 0.5 seconds.
Also it depends on chart type. Drawing huge facet with more than 100 cells in it can be painful while plain scatter plot on the same data works fine.
Currently taucharts supports scatter, bar (vertical / horizontal), stacked bar (vertical / horizontal), line. Also in beta we have geomap charts with customized map and parallel coordinates. There is a lack of documentation.. but we are working on this problem.