It is just my 2c here, perhaps many players will hate me because I post it this way .... but honestly speaking, I think it will make the game overall more fun.
The current epic gear market shows an interesting pattern: the low lvl epics (esp. useful ones) are expensive compare to their "store prices", upto 3x for some of them. However, as the lvl goes higher and higher, albeit the items are more and more powerful, the AH market price for them goes down gradually, eventually well below the store selling prices. It may look counter-intuitive, yet it is pretty natural if one think about the constant drop rate of all epics at their respective lvls. There are simply fewer and fewer demands from the fewer # of high lvl players who can use them. Yet, as lvl goes higher, you stay at the same lvl longer and longer (more difficult to lvl at higher lvls), and hence farm in the same area longer (approx.) ---- this, multiplied by the constant drop rate, you will simply have the result supply becoming relatively higher vs. demand. And hence the price drop, relatively. In addition to this factor, the fact that there are far more low lvl alts from veteran players than veterans themselves, and these lower lvl alts will all need some epics one time or the other. This again drive the demand for low lvl epics significantly higher. And hence explains the rise of the price of the low lvl epics, relatively.
The only exception for this is the newly introduced epics, while their prices will be kept high as long as there are not enough time for people to farm plenty of them yet. For instance, the gator is a very good example. However, following the trend of the other epics, gator's price will drop eventually when they were farmed enough.
This is neither "right" or "wrong", "good" or "bad". It is simply an economic consequence of the constant epic drop rate in NOD.
However, if, I mean, IF people feel this is a bit counter-reality (compare to, for example, large diamond prices in market, it is actually expontentially growing as the size grows.) and IF people want NOD eco to be closer to real world market in some sense, then we can fix this issue by a very simple method: change the constant drop rate to be a linearly(or other functional) decreasing drop rate, with the higher gears having less probability to drop.
However, obviously it is too late to do this for epics. But for future legendaries, this may introduce a more "equilibrium type" economy. For example, a newly introduced legendary "gator" will probably worth pretty much the same as the time goes on, as the in game gold will depreciate and more people will reach the lvl to be able to use them. How to fine tune this drop rate to keep the eco "exactly" at some "equilibrium" will be difficult. But it won't be necessary, probably either. A decreasing trend of drop rate will serve this purpose pretty much well enough.
Of course, there is no axiom saying that we should make NOD more like reality ---- after all, isn't NOD a getaway for us from reality first and foremost?
About drop rate of the future coming legendary gears
