Fun solution to Crits

I was thinking about what Riot Reinboom said he hated about Critical Strike: "And to be further clear it's not the RNG element that's wrong here; it's the RNG element compounded by the reaction window afterwards. RNG that guides strategy and decision making but doesn't define individual events are amazing (Bard meeps <3). Short response window RNG is the icky one."

So I decided to make up ideas for how Critical Strike could be more fun by adding a long response window to the RNG, instead of flat damage. This is just for fun, but I thought it was cool enough to show you guys.

Give everyone 10% Crit chance to start with. Reduce the Crit damage bonus to 50%

The following champions get these abilities:

Vayne: Crits make Vayne's next Tumble within 3 seconds turn her Invisible. Ashe: Crits apply a short snare. An enemy snared this way can't be snared again for 5 seconds. Kog'Maw: Crits activate his W. It's power is increased, it's duration decreased. Urgot: Crits activate acid hunter. Graves: Crits give a stacking Armor/MR buff (remove the buff from the passive). Yasuo: Instead of every three Qs being a Knock-up, a basic Q that Crits will make Yasuo's next Q a knock-up. Yasuo starts with 40% crit chance instead of 10. Tryndamere: Crits give a huge amount of Fury. Tristana: Crits on targets with E on them explodes the bomb and halves the CD. Ezreal: Crits reduce all cooldowns by 1 second (Landing a Q also has this effect right now, so landing a critical, max level Q would have a 2 second CD). Sivir: Crits give you a movespeed boost.

What do you guys think?