Well...they haven't exactly shown a desire to have that kind of dynamic item manipulation in D3. As a matter of fact, they totally dropped the ball when they had a chance to take things in that direction.
What I'm referring to is the shameful thing that happened to White items. When they first introduced leg crafting, I was excited about the direction I THOUGHT they were heading. I assumed that the quality of the White mattered when crafting. Thinking that if you had a +15% superior piece, it would roll into the craft. To my absolute horror, quality didn't matter at all. The quality was omitted entirely. As we all know, we don't even use the whites anymore because of the carebears who cried about having to find materials.
The above instance reflects the lack of desire from Blizz to have intricacies involved in our item manipulation. Instead, we just stand in front of a Mystic and tweak 1 stat line. A bit low-brow, if you ask me.
It's not because "the carebears who cried about having to find materials" it was because it's a stupid idea to begin with... Go look for white items that actually spawn in the hundreds in some area in act 5 and then fill your stash up with random items that you might some day craft but eventually throw away because you are running out of space because you have to horde a million of other legendaries in the hopes of them becoming useful one day because Blizzard changes skill balance and legendary affixes. See, the problem was not with the white items or legendary materials, it's with the whole inventory and stash space thing. It was retarded to keep it that way given the current system so they did a good job of removing it.
@OP: It's always been like this pretty much in every game but probably mainly in Diablo... Activity peaks on patch / xpac releases and then slowly fades then peaks again when new content is released. The only way to stay occupied with the game in my opinion is to play multiple classes and have friends to play with,