What if Ra is a negative entity?

[Minyatur]

Perhaps it's reductionist to say, but basically pure STO without any conflict is boring.  And incarnated life isn't supposed to be boring, at least in the opinion of those crafting the entities through which the Creator experiences Itself.  Like the Bard said, all the world's a stage, and men and women merely players.   Likewise, an entity choosing to be STS is little different than an actor choosing to play a bad guy so that the story's hero has something to do.  And like actors ending the production with a round of drinks at the local theater bar without regard for the roles they played earlier in the evening, eventually STO/STS reunite as companions as well.

To add to what you said, beyond the scope of individualization I'd say the STS path offers awareness of what you require to go down that path.

Does it require confusion for us to become STS? Does it require broken positive feelings? Broken hopes? Broken joys? Broken trust?

Each being that does is a mirror unto a play of circumstances that would've lead you to make the exact choices they made.