Some simple QoL buffs for Rengar

His empowered Q should deal true damage and heal himself for 50% of the damage dealt to deal with champions who buy Thornmail. Also, his W is very lackluster. The bonus resistances should be doubled, and it should deal an additional 10% of the target's maximum health to make up for the fact that it does no damage. His bola strike is also very weak. His empowered E should pass through units, rooting every unit it hits. Rengar should also get 20% damage amp on rooted targets. Lastly, his ultimate's exclamation mark needs to be removed otherwise he can't assassinate people, and he should also be untargetable so you don't get chunked in teamfights. It should also activate instantly so you can use it as an escape.

These changes will surely bring Rengar from the abyss of inviability he is in right now. A champion as mechanically intensive as him should not be so unrewarding.