Wooden Chests are somehow the rarest chests in the game

I have been messing around with a bunch of different chest times and recently did all the math based on current dungeon drop rates for some rather hilarious results that show that Wooden Chests are actually the rarest chests in the game.

This is for two main reasons:

1: Marks only upgrade and not downgrade. This means the only way to get Wooden Chests from marks is from wooden marks.

2: The quantity of wooden chests needed if wanting to open them every hour exceeds how many of everything other chest relative to drop rate.

Drop rates currently for chests, are:
40% Wooden, 29% Iron, 19% Gold, 9% Ruby, and 3% Diamond.

Assuming the player has 3 slots and takes the full amount of time written on the chest to open (it is a bit lower than that, but harder to calculate), it comes out to the following rates for 100 chests.

40 Wooden Chests last for 13.33 hours.
29 Iron Chests last for 29 hours.
19 Gold Chests last for 38 hours.
9 Ruby Chests last for 36 hours.
3 Diamond Chests last for 24 hours.

Relative to number needed to perpetually open chests, Wooden Chests are the RAREST of any chest in the game. The second rarest is diamond, which should obviously be the actual rarest since it is the highest rarity.

Would definitely like some kind of feature that would fix this, as currently Wooden Chests are lacking in ways to accumulate them effectively relative to how many of them are needed.

This wouldn’t necessarily mean to increase their drop rate, as they are still the lowest tiered chest, but something like more Wooden Marks from dungeon mark Wooden stacks or some other mode for early to mid game players that are completing out storyline that can target them would be great.

This issue can be solved if they add +2 extra wooden and +1 iron marks for every dungeon difficuly level I think.