Interesting. I usually have just one; so far only one test with two (different) characters.
I’m not a fan of the ActorCore look (especially the hair on female characters and no physics on the clothing); if I needed many people in the background, I’d probably use Alembic files and tools in C4D to populate the scene. The scene will end up in C4D anyway so I don’t worry too much about having multiple characters in iClone if the need for that should arise.
My big gripe with the CC3+ body isn’t the lack of polycount (since you can subdivide), it’s that the topology is rather basic. There are tons of tricks to get around low polycount or to have the topology do a lot of the heavy lifting in terms of deformation, but CC3+ doesn’t really take advantage of any of them (except the face, i really like the face topology).
