Just a random thought…
But would it be possible to deck/stack identical hero cards?
This game is based on grinding, and there are always duplicates.
If they are decked/stacked in the same slot, it reduces the slots required while people are waiting for for quantities, and allows for more to be generated, without having the need to increase the number of available slots.
I’m only thinking about virgin heroes, no modifications or upgrades, 1* and 2*.
For example, I have 3 Kenjiro, taking up 3 slots, while I wait for the possibility of more yellow heroes to come around (with no promises), and I want to get the 10.
They could be decked/stacked, and only occupy 1 slot (since they are identical). Much like inventory, which already does that.
Just a thought.