Glad to know you liked it ^^
I believe the confusion can be solved by this: traits don't dave die sizes. They are things that increase the die rolled when useful.
So, if using a skill d10 and have an applicabel trait, you roll a d12.
If two players have brawl d10, but one of those have veteran trait, it's stand to reason the veteran should have a higher chance of avoiding the risk.
While skills can increase in die size, traits can't but can be broken just like items.