I have no doubt that, as I write this, Blizzard's design team is busy working on putting together the set bonuses for Tier 18 armor. I've seen threads in other class forums about their ideas for the ideal set bonus. Why should they have all the fun? Let's help Blizzard do the next tier right.
So, say tomorrow someone datamined the set bonuses for paladin Tier 18 armor. What tier bonus would have you counting down the hours until you could trade your mythic socketed warforged in for the crappiest-itemized normal mode tier piece?