Kha'Zix new ult evolution timer

So, when you evolve Kha'zix's ult, you have 2 seconds of stealth and 2 reuses with 10 seconds total to do everything. You also have a 2 second CD before you can reenter stealth each time. This means that, after activating ult and using your first stealth, you have 8 total seconds of time already accounted for, with 10 seconds of total time to use it. Even if you cut your stealth times short, this feels extremely short and limiting.

Kha'Zix used to have 15 seconds of time back before the assassin rework that gave him his new Totally awesome ult evolution.

Riot, all I'm asking is for the timer for reusage of Kha'Zix ult to be extended upon evolution, it feels extremely limiting right now.