...figures are not the only elements that affect response. Props, clothing, and sets with high poly counts and large large/highly detailed texture maps also impact working in OGL mode (which is what you are in while working on a scene).
As you are noticing this with 6 figures in the scene, most likely you are in working 64 bit as I am in 32 and just one Vicky plus one Mike can slow things down to a crawl for me. If some of the figures are in the background you could reduce the Level of Detail a few steps.
I also often work in wireframe when I do have a large scene. It’s tricky but it saves memory and I’m already used to it because that is Bryce’s default view mode.
For rendering I usually render to a file rather than the viewport or separate window and set the viewport to bounding box mode to conserve as much memory as possible since in 32 bit there, is a finite amount of RAM available (usually 2GB).