May need to put a cap on crit.
With the rise of double IE as a viable build path on ADC champs and... well, Gangplank, you may need to consider putting a cap on crit.
Honestly, the fact that there isn't is dumbfounding. Logically, 100% crit shouldn't be allowed since having that is the equivalent of doubling your AD permanently (or in the case of Yasuo, 1.8x your AD). While being way more cost effective than just buying all the highest AD items in the game, this particular build also is basically the only viable way to get that kind of consistent damage output.
Even ignoring the balance issues, let's just look at it from a crit perspective - if every hit is a critical hit, then what one actually is? None of them are more powerful than another hit, so by all logic none of them are really critical hits - they're just normal hits next to one another.
I know you're reworking the AD items come preseason, but if you decide to keep crit as a stat in the game, please - at the very least, max it out at 80% or so. That way it's actually a critical hit and not just another hit (while also being very cost-effective free AD).