Unpopular Opinion: Remove Rengar's W healing
Riot, look, if you're not going to nerf his damage the least you could do is remove this dumb mechanic.
An assassin like Rengar should not be able to survive an entire damage rotation to then further heal it all back up. This is like Pyke's passive but you don't need to be out of vision. If you're gonna revert his rework, do it completely. Old Rengar never had this bullshit and it was balanced as it was. It used to give temporary armor and magic resist based on the amount of enemy champions hit which allowed him to tank a bit of damage before being taken down. You can keep his CC cleanse but for god's sakes, just please take him out of the top lane.