I agree sets are pretty useless.
I have 3 sets of legendary/green items myself,and,don't even use them. I just keep them in my stash.
The only reason to keep them is because they are rare and you can't get them on AH anymore.
Leveling up is ridiculously easy as well,but,that doesn't bother me.
grinding can be tedious and boring especially if your looking for something specific.
But,as i said,i like this game and am looking forward to future expansions/sequels.
The only set I've really used was the Firebird's Finery which gets a huge damage buff when you complete it. I've heard that it's not the greatest but it was good enough for me.
I have a beefy monk in the current season without any completed sets but I've been on hiatus due to work.
[Edited by Neo7, 10/23/2015 1:36:06 PM]
Bought it right now, never really played any Diablo game before.. I hope I like it.
One thing I understood from the vids I saw is that this game series have an epic lasting Appeal, people reported they are still playing even Diablo II.
Well It's confirmed not only I like it I love it and I think I'm hooked.