Reworks are awesome.
I'm not even talking about when they go sideways and make the hero worse - that can always be improved.
I'm not talking about full new hero reworks like what we're going to see with D'Va and what we have with Tassadar.
I just mean taking old, dated heroes - or heroes who's designs are prohibitive to being viable (too good or too weak)
Diablo's rework is a great example.
My personal wish-item is to see Tyrael get a rework. He's one of my favorite heroes but he's quite obviously a product of alpha/beta HOTS design principels.
His trait is the obvious contender, but I'd love for him to become an actual tank somehow.