First thing's first: We're removing Akali's ability to hide from turrets, which has been the most contentious part of her update. Many of you are asking why it took us half a year to get here, and the answer is that Akali depended on turret stealth to dive as effectively as other assassins. Ultimately, though, Akali has so many strengths (the ability to switch targets mid-fight without giving up kill pressure, and four forms of mobility, among others) that she doesn't need to also be a reliable turret diver. Given Akali finds better success in longer fights than other assassins, the short duration of turret dives make sense as a weakness, which they now are. The cooldown nerf is simpler: We're reducing Akali's late-game access to Shroud's defenses.
With that out of the way... Five Point Strike nerf. Akali's become blind-pickable in higher echelons of play and Q's heal is a huge part of that: PvE sustain lets Akali survive matchups where she should be getting shoved out of lane if not outright dying to aggression. We're giving her more health regen to soften the blow, but are well aware it's a power-down overall.
We'll be keeping a close eye on how Akali lands in both pro and regular play (did the W change reduce frustration? Did the Q change open up meaningful counters?) then decide on how to bring her back up. In the meantime, you can probably stop permabanning her.