Suggestion: Cross Traits based on Skills
Currently traits from other classes do not affect your current class at all.
I believe they should implement a system where the more cross skills from a different class you equip to your current class, the more that classes traits affect your current class based on a percentage.
For example, to make things simple let's just say Pugilist has just 1 trait, a trait that increases Physical Attack by 10, and you're currently playing as a Gladiator. You equip Second Wind, a Pug skill, and you gain 1 Physical Attack. You equip 3 more Pug skills, and you gain 5 Physical Attack from that trait.
Something like that.