My feedback:
Great idea on higher droprate for higher levels, I've proposed that in the past and it helps deal with throwaway level 20 botting accounts farming 24/7
Also great idea on the cloak, people who collect those will have to farm event and pay something out of their own pockets if they want to obtain it, and this time they won't get cucked by RNG.
Drop rate seems low, but as you say in this thread you are still collecting data and you may change it eventually.