Traits do incentivize you "acting" a certain way (picking up dialog options that are otherwise inconsequential to the world). That the heartless bonus is useful only to backstabbers, and not mages, doesn't incentivize at all to make a heartless mage or warrior.
The crux of the disagreement is simply defining what roleplay is.
I think that if I set up my characters as having specific personalities right at the beginning of the game, having to change their "personnalities" to get the best bonus is harming the RP process.
In other words, the game incentivize you to pick personalities that match the best bonuses for their class. That's anti-RP in my book.
I have no qualm about my suggestions, I know there's different ways to adress the minor game's problems.
But if you are starting to envision a system where non-combat skill can be enhanced through a special gearslot that is non competing with combat stats, it is a slippery slope to my system ^^ (which is basically a non-competing point system for those non-combat abilities).
