How much harder is rengar than kha'zix

So k6 has always been one of those low elo stomp champions and good in high elo. I'm a bronze IV scrub but ive got his early game down. I gank lvl 3 if I can. Is someone's over extended, I'm coming. In a recent game I went 28/9. Rengar is also a major stomper if he. gets fed. He's still the scariest jg. Fed rengar op. I permmaban. I tried and failed at him last season multiple times. I did hear that made him a little easier to use but he has I higher skill ceiling. K6 and rengar have been drawing alot of attention and causing a ruckus. More so rengar because his q with full ad one hits and tank rengar oneshots. Fair and balaced totally. I main k6 currently since he works for me even though I'm bad at the game but I've learned him and I've been commuting mass murders. But I'm curious about how much crazier rengar will be. Also how much harder is he because I want a backup for of k6 gets picked/banned with a simular playstyle.