I think in general the activity's average calculations come from the girls beauty, charisma, fitness, and sex skills. From this skills 2 primary and 1 secondary skill calculated, and 1 ignored. The primaries are weighted more than a secondary (maybe count as double). All activity requires different primary and secondary skills.
I found this post earlier about this:
https://f95zone.to/threads/porn-empire-v0-9-pedev.2857/post-12221662
As you can see the green blocks are the primary skills and yellows are the secondary.
I think the photomodels same as the hostess and the videomodels same as the strippers.
But I'm not sure whats the profile of the camgirls. Maybe the beauty+sex and charisma, or beauty+char and sex...