"Smart loot" in D3 was only needed because the drop rate of anything worthwhile was so low to begin with. Instead of "smart loot", they could have just increased the base drop rate enough to where you get just as much worthwhile loot for your current character (in a post-RoS world where all trading is banned, this wouldn't have hurt a thing). Then you'd still be able to get items for characters (classes) other than the one you happen to be playing at the moment - a very common Diablo playstyle that "smart loot" completely broke. "Smart" loot was a dumb way to fix the problem, and by the way, I have put hundreds of hours into D3 both on original release, and after RoS release.