As you mentioned, key ideas need to be identified to a greater extent compared to themes.
The collective human experience in The Crucible is that of mass hysteria, related to the human emotion of fear. For instance, the people of Salem become irrationally afraid of witches among them, resulting in false accusations and subsequent executions of several people in the town. You may perhaps choose to cover the "society" aspect as part of the experience of mass hysteria.
Mass hysteria is also perceived through instances of mob psychology, which is a process through which people are deprived of their individuality and their perspectives and beliefs are altered by a crowd. This is seen in Act 3, when Abigail convinces the girls in the courtroom that there is a yellow bird above them preparing to attack. We are told that all the girls scream and cover their eyes, although the audience would be aware that the bird is imagined as it is something evident to them. Mass hysteria and mob psychology are described as dangerous human emotions and experiences because they obstruct the truth. You may therefore wish to explore individuality under the concept of mob psychology and examples thereof.
I hope this helps!