Summary
Allow for better support of Mythic drops. Allow for selecting specific tiers of items to drop instead of just random ones.
Usage
It would allow for drops for mobs to be better defined.
Value
Overall, it would allow more people to use the drop tables and drops for mobs because it wouldn't require them to make their own items, and with the plethora of items mythic drops has, it will enhance anyone's server that uses both.
Priority
I'm a bit biased in this, but I'd place it in high priority, as my server will soon be launching, and I want as many things to be perfect for my community as possible.
Implementation
Just changing how it handles mythic drops command. After all, you can give people specific tiers of items through their own commands, why can't you make them drop from mobs?