This is not a traits fault really (I mean slightly, yeah, sure), but it is really the Mischief skill interactions. Any trait can autonomously use certain/if not all Mischief skill interactions. And only some traits have a preference to be more inclined or less inclined to do them.
Like a Mean/Evil Sim has "8" priority to scare another Sim, Insane = 6, Child/Teen/Goofball = 3, Childish = 2, Proper = -6, Good = -10. The rest are pretty much like neutral/0.
Relationship matters like if Enemy = 3, Disliked/Despised = 5, Various Romantic = -3, etc.
Mood plays a part too, Playful = 5, Confident = 4, Angry = 3, etc.
But IHMO, yes, all actions such as Mischief should be better target for only certain traits or those who like Mischief! Utilizing whitelisting and blacklisting (an internal file tuning filter) certain traits (like/dislike are internally regarded as traits) from using these interactions.
TLDR: Yes, they need to do some reworking!
Thanks for delving into the technical aspects of things there; it's helpful to know these things when coming up with possible solutions
So if I'm understanding that correctly, the final priority for an interaction is calculated by adding up all the bonuses and penalties? Because if that's what's going on, I think the Goofball's Mischief obsession might in part have something to do with them being playful a lot. For that particular example you gave, a playful Goofball with no other factors would end up with a priority of 8, on par with the Mean and Evil Sims. Presumably even worse if the Sim happens to be a child or teen (literally turned up to 11 in that case)
I have seen lots of Sims autonomously use the interactions, even Bella Goth on occasion, which is amusing in a random weird way. But the Goofball Sims I've seen seem totally obsessed, like they can't get through a conversation without inevitably resorting to mischief and making everything awkward. Not counting any other life states' special ones, their favorite Mischief interactions in my experience seem to be mainly "scare", "lie about career", "ask due date" on non-pregnant Sims, "start preposterous rumor", and sometimes "noxious cloud". Sometimes they'll continue with the Mischief even when they've already become embarrassed and dig themselves even deeper. </3 Not sure what's going on there
Anyway, if they could find a way to give the priority bonuses more nuance, that would be great. Like make the moods affect priorities differently for certain traits. For Goofballs, I would imagine their Mischief interaction priorities could be set mostly to 0 by default, if not all of them. Funny interactions on the other hand could be set on average to whatever priority they have most Mischief interactions set to currently in the live game. If they're feeling playful, they could get a small boost to some Mischief interactions' priorities, but a much bigger boost to Funny interactions, so they're much more common. Playful Goofballs would become massive hams, as they deserve to be. Angry Goofballs, however, could be more prone to Mischief interactions, particularly the more "mean-spirited" ones
On the other hand, you could have things like Evil Sims with the Playful mood getting a tiny boost to Funny priorities, but a huge boost to Mischief priorities, especially ones like "scare" or "describe apocalypse"
Sidenote, I find it odd that confident of all moods is giving a priority bonus there. Going on a pranking (or scaring) rampage just because one is feeling confident sounds kind of random for Sims without a blatantly "malicious" or "mischievous" kind of trait
