25 keys per week is the thing that is most annoying me in this game.
I play as a tank, my wife plays healer. And we have to cherry pick which expeditions to join because we nearly always spend the weekly keys. We have friends that play with other friends of theirs and by the weekend, they have no keys left to play with us.
The key/entrace mechanic is also full of bugs. You lose keys by simply teleporting into the instance.
If someone is already on their last key, another person cant fill the spot for someone who got disconnected.
Sometimes you recreate the instance and its already started, making everybody lose a key until the entire party is recreated.
Get rid of the keys. Add a weekly cap of umbral rewards. Let us play without restrictions and so many bugs.