Akali's ultimate should ONLY work on enemy champions.
https://www.youtube.com/watch?v=BTX3ErGXwIs
As you can see, she carelessly engaged on me, I decided to punish her by ulting her to my tower, she tries to use her escape, MISSES, gets lauched back since you cant go over Azir's wall, gets hit by 2 turret shots and before the third one even got launched, her last R was up and she was able to not die because her ultimate can be used on anything.
I mean come on, at least give her some kind of weakness. She already has 4 gap closers (5 if you include flash), no mana costs, built in sustain, a second flash, a slow, and even an ability that makes her invisible meaning if you tried to cc her you cant even see where you're landing stuns (you aren't always gonna have pink wards on you). If you were playing Katarina, and repeated this, you would be dead, since it only takes one mistake to die.