Here's my idea for a check: imposter Blissey with safety goggles. They prevent bliss-bliss from taking annoying weather damage, and of course, they block spore. They may be more useful than eviolite.
I don't like the idea of dark void in the metagame. I think that this has been brought up before, specifically by ntiller. He talked about how it is bad to have to choose between two moves, one which is luck based but gets around a specific check, and one that doesn't. I wholeheartedly agree. After a certain point, more luck is always worse, and all Pokemon metagames have reached that point.
I also hate prankster topsy-turvy. This move alone makes set up sweepers useless. With unaware, you could always predict the unawaremon staying in and go for taunt or spore. With conventional prankster, you had to beat them in a prediction game. These days, you will have to run priority that can deal with the opposing topsy, which severely cuts into what you can do with set up sweepers. Even if you pack spore to cripple the topsy, they can switch out and abusers the new sleep mechanics to wake stuff up. Now, I am not saying that topsy turvy is too strong, I am saying that it imbalances the metagame by killing all set up sweeping attempts. I think that it is too early to think about banning things, but if there is one thing that is more banworthy than anything, it's that god damn topsy-turvy.