Item Drops

Maybe it is just me but I am noticing that the random item drops is being to random. Like for example I start the next difficulty mode on Act 1 and the enemies are dropping items that were dropping in normal act 1. I am fine with the random element of white items, magic items, unique items etc...but I think they still should at least scale with the level of the enemies your fighting or else how do you really know where to farm to improve your gear?