AP Champions
I feel like riot is intentionally making an effort to really put a stop to AP Champions. They hardly ever increase any ratio's with AP Champions, and Riven just got a health regen buff. Granted, this buff isn't a lot, but its not like they're nerfing her. A good amount of the champions in the 5.24 Patch were AP champs. I don't know, I sorta feel like season 6 is going to shift a lot towards AD considering they introduced new AD items and even buffed a few of the previous AD items. Not to mention they keep increasing the prices of AP items and lowered the AP on some items such as Triforce.
For those of you who might complain that I'm wrong, these are just opinions, nothing to take to heart.