I see people attempting to come up with ways to remove how poorly one can be treated by the RNG in the game and how, given personal experience, you can wait all tier long to get that one item to have it only drop once and it be the night you were away. Given this I've tried to come up with a way to help out bad RNG.
What I propose is adding a vendor who is able to sell any piece of gear that drops from the raiding teir, you can add 4 and keep them selling the same type or just load one with them, but lock the gear behind two very important barriers to prevent getting gear beyond ones own means. First being that each boss would always drop a stacking item, let's call them motes of awesome, and once 10 are collected they can be combined to form a crystalized awesome. These would have their own ranking. For example LFR motes wouldn't stack with flex motes and when combined you would for a crystallized LFR awesome, or other. This is done to prevent gearing at a super high rate by simply farming and using them to buy heroic gear.
The next barrier to this would be locking each item behind each character needing to have downed that boss in the needed difficulty. For example if boss A drops the weapon you want in order to buy it you need to have downed the boss in the difficulty you wish to buy it. This would stop people getting the crystals and buying the best items then weapons as fast as they could. This could also allow for scaling the power of the items drop in the raid maybe making them stronger as you progress later.
Let me give an example of how this would work, this example is taken as heroic raiding. A paladin who has been raiding has yet to see a drop or win [Britomart's Jagged Pike]. With this system they would be able to get the idea by doing as follows. they need to have 10 motes of awesome, they then combine them into crystallized awesome. Next they need to have beaten Thok on heroic. Finally they pop off to the vendor and get the gear. Maybe at a later stage a vendor could sell an item to upgrades an item to warforged for say valor, making choosing how to upgrade more interesting.
All in all I feel this is a pretty fair way of protecting people from streaks of bad luck. By locking it behind boss kills and a reagent allows a pacing mechanic and also a way to make sure that whatever you buy was actually earned. This also means that people will feel a greater urge to keep playing older bosses on farm since even if you have all the drops the boss drops the motes you earn will help you buy the items that may not have dropped. Thoughts?