Just curious, why the Oracle change?
I am trying my best to take a second, possibly more inspired look at Elements and I am trying to eliminate sources of frustration, while keeping the game challenging.
Not getting a card from the Oracle can be frustrating and it does not effect much the balance of the game, since it is just once per day.
Also, sometimes I tend to be conservative when adding new features, since having to decrease rewards later is usually quite traumatic (more frustration). It was time to increase a bit oracle and arena deck rewards.
I also have in my head a second approach to that "hated card" idea in the trial but I am still working on it.