I should add that I have only been playing 3 & 3.5 months (2 accounts). Anyone with a lengthy play and loot history is going to have more varying results.
I have already seen the Compass to Gloves disparity. Especially when you consider that starting out, you aren’t going to be able to complete the Legendary challenge stage, creating a further imbalance because you will always get a compass, but never gloves from a challenge event.
Not well thought out at all. Or maybe it was, as a conspiracy person might claim. 
I might take a look at the Seasonal Events as well if I can find screen shots and see if the same problem exists there. With the Christmas event, there was no way I was going to reach the 4k award (the rings I need) with a 3200 team.