Rengar New Changes Idea

For the upcoming rework for I have had an idea for his new ultimate that would be a game changer. Now my idea is that his ultimate is a stealth toggle that he could has at level 1 such as or . Now it sounds op but make it so he can't use abilities while in stealth and have a fade in time such as 1.25 second to fade in then he can use abilities. Also his ultimate would not have his leap passive he has now, it would be more of an get behind the enemy and assassinate them, but the damage would be a bit toned down with the rework.

Level 1 (1 point), 1.25 second fade in time and 30 second cool down Level 6 (2 points), 1.10 second fade in time and 26 second cool down Level 11 (3 points) 1 second fade in time and 22 second cool down Level 16 (4 points) 0.85 second fade in time and 20 second cool down

If you need any more details just ask and thank you for your time.