Hello Fatshark,
I have played Vermintide 2 a lot over the years and one thing that stood out the most, was how welcoming the cataclysm community was. I think that was in big parts, because there was nothing to earn in cata other then the experience.
Please don’t reward people in Darktide for playing the highest difficulty, because that would risk the community of becoming as toxic as in other games/Legend difficulty. Playing a difficult game should just be the reward itself.