How about making Ezreal Q have a chance to crit?

I was thinking why not put a passive on his ult where after putting a point into it, Ezreal's Q has a 10/20/30% cap on his chance to crit and a 50% damage bonus on a crit when using his Q?

In other words, if you have 8% crit with one point in your ult, you get 8% chance to crit on a Q. If you have <10% chance to crit with one point in your ult, your Q's can still only crit up to 10% of the time. This way, I don't feel bad about buying crit items (like IE or shiv) instead of damage with a better passive for Ez on it (like Bloodthirster) and then later complain that my autos are entirely useless because I lack any crit or attack speed other than trinity force.

Obviously, the numbers can change, but you get the general idea.