As one of the lucky players of gw2 i got a permeant Bank access from a black lion chest over a year ago.
I know feel cheated by the chest every time a one time use drops and there is not use for me.
My suggestion is to let us trade these in for something, even if its 5k karma just so when i get one out of a black lion chest i dont feel like welp that useless.
I would like to see other things be traded in for some minor rewards, like old account bound minis that drop from chests more then once, mini queen jenna and one time use tp/merchants/bank access.
the reward could be as simiple as 1 to 10k karma just something so i dont feel so cheated by the chests