What if, at the end of all of the trials, the final loot crate mixed into its loot pool any legendaries that are available to the player that are not otherwise obtainable outside of specific quests or farms?
E.G. the Bekah is from completing challenges. You can get it once per character. Rico is a shield for a quest late in a DLC quest chain.
Would these things being available at the end of trials make you want to play them more? Would you be grateful for a legitimate chance to get otherwise (or nearly so) “one time items”?
What about DLC’s? GBX could add dlc stuff only for dlc owners, or they could even make the very small chance per longish farm item drop…which might even entice a customer to purchase the dlc because they like the item?