I guess my main issue with the Lockers is the value of buying the item is not in the same value of the rate at which it drops. I.e A Red item is worth 7500, therefore, I would expect opening 7500 worth of lockers I would expect to get one red. The pay off is pay 7500 and get a red you want, or spend 7500 and get a random red plus a bunch of extra common junk, maybe even luck out and get some extra nice loot on top.
Unfortunately, the cost is not equal to the chance and once you cap out on level, the current rate of income of Veritanium is not economical to support either spending outright on cosmetics you want - especially mythic quality. Either the rate of income needs to increase or drop chance should increase.