Make ability indicators correlate with their ability hitbox's.
Meaning, Blitzcrank's hook model should be as wide as its designated hitbox. A champions mechanics shouldn't be deceptive to the eye like this, and a ton of champions also benefit from the "even though it clearly shows I didn't hit you, in reality, I did".
I'm sure you guys are going to post more champions below that are complete nonsense via shitty ability indicators, but I'm just using the most popular one as an example.
ult imo, I like "bm'ing" outside of her range (same as 
Q) and sometimes I'm way outside of the indicator and it still hits me