One problem I've had for ages is that when I make a customized encampment leader with a lot of traits, they lose the ability to gain new traits on level up. For example, I might start them with a bunch of traits (e.g Btf, Unp, Ldr, Hpn, Agile, Elemental (Water), Magic (Nature), Cunning, Creative, Band of Sisters, etc.) and then upon level up, I can only select from the list of Aspects, never traits. Even after leveling up many times and selecting the max number of aspects, I still never get offered traits. Other Slavers receive traits normally, being able to select super useful things like Flying, Fleet, or Sneaky, so it really sucks that I can't get those for my encampment leader (especially Flying, I want it so bad ;-; )
It may be some problem with the In-game trait counter, because in the past I've found it to be totally inaccurate at times (though I havent checked it in recent patches).
My main theory has been that it's due to traits like Unproven and Band of Sisters, which disappear immediately after character creation. Maybe when they subtract from the Trait counter at the very start of the game, it somehow messes it up? Could be completely unrelated, though.