I decided to see if I could do a procedural crowd scene with Geometry Nodes in 3.0. Please feel free to download my Blend and see if you can make this better! (Note: many of the nodes I used are the old ones that will be removed in future versions of Blender. You'll need to enable "Geometry Nodes Legacy" in the options to get this working in the current 3.0 beta.)
The model is from BlendSwap, adapted slightly. The animation loop is from Mixamo.