Hi, this is Yoshida, the producer/director.
Regarding rare drops in the Bowl of Embers (Hard), in patch 1.20 we will be adding new methods to obtain the highly-sought after weapons when defeating Ifrit multiple times.
Of course, we looked into the idea of placing the weapons directly into a player’s loot list, but we were worried about unscrupulous actions taking place while players sort out who gets which weapon. (Although /random will be implemented in 1.20)
In 2.0, we will be implementing a Need/Greed/Pass system for item distribution, but it's very difficult to implement with the current server structure, which we tried very hard to do, and I’d like to apologize for the continued inconvenience this is causing.
This is similar to the OP's suggestion, but we have decided to preserve the current drop rates for weapons and individual chests. And in addition to the reward weapon, we will introduce an item that can be traded to an NPC for a weapon. This new item will drop at a fixed rate, and will be loot list-tradable, so you will have an opportunity to pass it to another player. (Updated on 11/22, 6:45pm PST for clarity)
This system will be used for every primal battle going forward. (And if we tweak the system, the changes will apply to every primal battle) Of course the drop rates and items necessary for trading will be different for each battle, so please keep that in mind.