I think that the discusion is too ban-happy right now. If we're discussing a lot of bans, we may end with 25 or so bans in 1 year or so, in a tier where in many cases, it would be unusable, which crashes with the spirit of OU. I know that UU and RU but those tiers are secondary compared to OU (and the majority of BL are OU viable, at least in Gen VI).
I think that we had to wait until PokeBank and wait a few weeks more to see what happens to the National Pokedex and with the unreleased Mega Stones*. I will say this because Tapu Lele may have a problem with some Fairies that are currently unreleased (like Mega Altaria or Mega Gardevoir). I think it's the case of Tapu Lele.
And of today, I doubt that Tapu Koko is broken. It's Speed is really high, but 1) Its Main Physical STAB Is Wild Charge, that causes recoil and it's only 90 BP, 2) his physical coverage is resisted to non-STAB Brave Bird and U-turn, none of them covering 3 of the 4 types that Wild Charge can't, including the one that is inmune (and it doesn't cover Ferrothorn, who at least has Iron Barbs). 3) It only has Base 95 Special Attack, not 130 and 4) Only has Thunderbolt, Thunder, Dazzling Gleam (not Moonblast), Grass Knot and Hidden Power. Give it time to at least stabilizing the metagame.
*I doubt that missing Mega Stones would be unreleased long after PokeBank is released.
Quick Bans are an EXCEPTIONAL method of dealing with bans when it was so obvious that they broken and make the metagame unplayable (Mega Salamence in ORAS OU, what was worse than XY Xerneas in Ubers) or it contrainsts the metagame too much (XY Mega Kangaskhan, XY Mega lucario, BW Shaymin-Sky, SM Zygarde-Complete).
And Hoppa-Unbound is an event Pokemon that has 680 BP and its allowed to have an item. The rare thing is why is in OU (it is because of his really bad defense).