Cool downs on some passives

People are complaining about zoe a lot mostly because she can 1 shot and do 20 flashes with her w but maybe give her w a cooldown every ability she gets? A flash is 10-20 seconds of not being able to grab spells and so on with other spells. I think riot is already fixing her e by making it not land on the ground which is nice and kinda fixes the problem with her damage. (idk the full thing with zoe's new fix but that's just what I skimmed over) As for other op abilities how about Rengar gets a nerf with his jumping bush to bush while he's in bushes that are not in the jungle he has a 10 second cool down that way us folks in lower elo don't see Rengar adc and get ruined by him. These are just small ideas I have for helping some champs not be so op. If there are other champs that have kinda op passives that should have cool downs I'd love to hear about them and see how they can be fixed. But all in all this is just the ideas of a player who hates getting 1 shot by a adc Rengar and hearing people complain about Zoe even though riot can easily fix her.