Living Story Achievement Rewards
Those items could become available in the achievement panel with unlocked weapon skins, because those items are mostly bound to achievements (balloon = 30/30 hot balloons achievement, torch = 4/4 torch runs), it doesn’t even take more data in the database.
Home instance! Decorative items like the Zephyr Sanctum model and the balloon would look lovely if kept inside a player housing area. Then the home instance would be a greater reflection of the adventures and history of your character rather than just a small glimpse of characters from the personal story.
The ability to add items like this would make your home instance really worth showing off to your friends.