I think the next rework/update needs to be for hitboxes
Hitboxes such as...
(Q)
(Q)
(Q)
(Q)
(W)
(E)
(Q)
(Q)
It feels that as if there's some sort of code in-game that if you side-step the skillshot even by just a small amount the ability will just lock itself on you. I can say that this happens occasionally when facing all of the above.
There needs to be some sort of update to the ability indicator of how big the radius/hitbox of the ability truely is because as of right now it's not accurate and it's misleading. One more issue that I found is that some abilities go through minions (acting like Lux Q) and this happens with Thresh Q (it happened twice to me).
One example of a misleading hitbox
##(Btw sorry for the bad quality, the league spectator doesn't record in full 1080p even if the graphics settings are set to the highest)
Notice how the shadow and the ability visual itself are pointing to 2 complete different directions. So it seems that if you get hit by the ability visual itself or the shadow of that ability you will get hooked regardless.
I would of found more examples for each of the champions I mentioned above but only a limited amount of my match history games can be replayed for me to record further footage.
(Q)
(Q)
(Q)
(W)
(E)
(Q)
(Q) 
(R) ,
(W,R),
(Q),
(literally every ability).
(Q),
(E). The list goes on but these are the biggest for me in addition to the ones you mentioned.
E yet?? The particle is only a few pixels wide, yet it will hit any champ within a 10 stack cho of the particle
nr nr nl nl uyu qqq MOOOOOOOOUOOOO aw aw rabbit rabbit, MOOOOOO * choking * ooooo, NURTRTRTRTRTRTRT Nrol Nrol Prellll
R needs to be bigger. If you watch the animation in slow motion, his arms will pass right through enemies and it won't hit. It's actually stupid. There have been way too many ults that should hit that just don't because the skill shot is thinner than his actual body.
(Q)
Q and
E possibly the worst three hitboxes in game
(E). I've ALREADY made numerous amounts of threads in the bug thread to get her shit fixed, I've posted SEVERAL videos displaying the inaccurate hitbox it has, and yet riot just ignored me. I don't play her anymore cause' of this (and her update, which was seriously uncalled for).