The only way the bryce render will get any faster is to Dump the current Erice wenger raytracer and install and modern day adaptive raytracer . BRYCE Raytraces ALL elements in its scenes including those element that DONT require rayrtacing, that being any NON reflective surface or NON refractive surface such as wood and stone. the problem is compounded exponetially when activate Volumetric lighting in bryce and makes volumetricly lit animations of any length almost impractical. Cinema4DXL uses an "Adaptive hybrid raytracer/ scanline renderer from Cebas. It determines what scene elements need raytracing and does NOTraytrace items that dont need it This simple scene( Pic) has one Volumetric visible spotlight and 2 fill lights and rendered in just over two minutes on my OLD 300MHZ MAC G3!! Adaptive raytracing is the only practical solution IMHO.

My website

YouTube Channel