idea to possibly rebalance Pyke passive

So as many of us know, Pyke's passive is extremely forgiving in terms of survivability especially in the case of assassins, well I was thinking maybe do something similar to Rengar's roar, where pyke can heal back damage that has been taken in the past handful of seconds, however it could work like this

the amount of damage he can recover is reduced bit by bit so long as he's in the enemy's view, however, there's a timer that requires him to be out of combat for X seconds before he can start healing by his stealth.