Hi,
If you're working with GraphicsLayers then you should deinfitely be trying to use the hardware accelerated display capability - either via the map property to affect all layers in the map, or if you still need some animated/custom symbols in your app then you can use the AcceleratedDisplayLayers group layer for the majority of your layers (inc Tiled, Dynamic layers) and keep the number of layers/symbols rendered by the standard WPF map rendering to a minimum. For any symbols not supported you'll get a "Symbol not serializable to JSON" error - in this case you should investigate switching those symbols to one of supported symbol types (primarily SimpleMarker, PictureMarker, SimpleLine, SimpleFill).
The accelerated display was specifically designed to improve the performance of graphics. The improvement in tiled and dynamic layers is marginal since most of the overhead is in rendering the image on the server or downloading tiles/images but it is still worthwhile. We've made further advances in the accelerated display since v1.0 in performance and in layer/symbol support and you'll see those in the forthcoming 10.1.1 release.
Cheers
Mike