I don't have one favorite "faster grass". Bigbraader's grass is my favorite grass, the one I use the most often. Complementary, sometimes I use Willi's grass (from C3D), sometimes I use AsileFX groundcover package (not their grass package, that's very slow to render), sometimes I use Linda's grass (Lush collection, in C3D).

Regarding twigs in my images, those I made myself. It's just some twisted thin cylinders, textured with a flat brown material. I modelled them in zbrush but they could be easily done with booleans in Vue.