Overtuned champions

http://matchhistory.na.leagueoflegends.com/en/#match-details/NA1/2350773155/26570414?tab=overview So I start off game 3/0/0 vs xin top -- after having to flash early to escape kha gank. I roam and use tp to help bot get a lead while still keeping control of top and being ahead of xin and able to 1v1 him all game long. In teamfights, I land 3-5 man ults every time. I do my best to peel kha and xin -- landing slows and using my q to burn them down. You'd think with I would be able to melt kha with my full combo -- especially with adc or mid damaging him too, but nope. If kha can tank full rumble combo, full adc damage, and exhaust and leona cc in a 1v3 while his team deals with my ult (on them and kha), malph and lb there is a problem. Mr is too damn strong. Look at how much armor pen items there are. Look at magic pen items. Look at who is naturally tankier (kha>lb or rumble or adc for tank stats naturally). Do they really need better resistance items that give more damage and passives too? Either nerf the champs, or the items because they are straight up broken. Both give cdr, 45 resistance (armor or mr) but is a 2.5 sec stasis really equal to a 300+ mr shield when you get low, plus bonus ad and lifesteal? I mean kha sitting on equalizer, tanking my q and e and killing me from full hp despite good use of zhonya when he's fighting from 1/3 hp is kinda stupid if you ask me. And it's not just me who thinks they're a bit overtuned. Challenger tier streamers have commented about how rengar and kha are way too strong compared to the other assassins. So please, either reduce their power and/or reduce power of their resistance items.