So as of 1.1.10, Test Subjects can have Positive or Negative preferences to different partners, experiences, and interactions.
My suggestion is to expand this into different tiers, up to 7.
From most liked to most disliked, these tiers would be Favorite, Love, Like, Indifferent (could also just not be listed in a preference inspection), Dislike, Avoid, and Hate.
Currently (24 Feb 17) Positively-preferred things will get the subject closer to orgasm faster. Indifferent things still stimulate, but not much. Negatively-preferred things don't do anything.
A related suggestion to the above would be to make it so the more liked a thing is, the faster that thing will bring a subject to orgasm. Things the subject is Indifferent to won't help towards orgasm, but may still slightly build Arousal and Anticipation. Exposing a subject to Negatively preferred things would have negative effects, instead of just doing nothing. These effects could include pushing the subject away from orgasm, lowering Arousal and Anticipation, causing pain, extremely affecting Anger/Intimidation, and in the case of Clients and Volunteers, cause them to quickly terminate the session. The flip side to exposing a subject to more-disliked things, especially Hated things, would be a very large production of Scalium.
One final suggestion to build onto this (assuming there will be a way to inspect subject preferences) would be to never show Favorites and Hates, instead showing them as more-neutral tiers on inspection. This would require the player to still ask questions and find out things about what the subject enjoys and doesn't. You could instead have inspecting Favorites and Hates locked behind a late-game, expensive upgrade to the Personality Inspector. Another option, or perhaps addition, would be having to spend some kind of resource to find Favorites and Hates, or maybe just have some kind of resource spend to find out preferences in general.
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