This trait gives you 3 negative points and give -2 dex -1 strength -2 int -1 perception -5% speed when in 20 tiles of any giant spider
Oh dear, how it would suck to have this trait given the large amount of spiders wandering the wilds. 
That said… I am all for this. Although, might I suggest a decrease in stats happen only if one actually sees the spider?
A spider could be out of the player’s sight and, it wouldn’t really make sense for the penalties to apply then.
i like your thinking! it really does make sense better if you can see it.
I think that it would be nice if overall speed was decreasing and movement speed increasing depending on how close a spider is.
I would rather get buttsexed by an npc than have to fight a giant wolf spider IRL.
Someone way earlier had a great idea for phobias/likes and dislikes, they would take place on a separate screen and use different points. If you had a “phobia” of spiders or “hates” or “very dislikes” spiders, it would do something like this, and if you had arachnophilia (morale boost) or “loves” or “very likes” (stat boost) you’d get a penalty for killing them, but not for being around them.
Something like that.
Yeah, this seems like something that would be very similar to GlyphGryph’s planned likes/dislikes system (link), which should hopefully be start being worked on once GlyphGryph gets free from managing the kickstarter.