The only way you'll be able to redraw your chart's GL view is to use the method you mentioned. When you call this method the chart has to rebuffer the entire graphics layer so that explains the performance issues you are seeing. At the moment we are revamping the entire graphics backend to fully support data streaming so impovements to this may well be included in a future release. I have added an issue into our backlog as this is definitely the right time for us to discuss this.
As for series style animation, this isn't currently possible either, but this is a good idea and I have added this onto our backlog as a feature to investigate so this will also be discussed in the future.