What if we could buffer abilities?

I'm not talking about Input Buffering, where you use an ability on someone from a distance, and your champ then walks into range before using the ability.

I'm talking about when you're currently being in range, having the ability ready to cast on a specific target without needing to select the target a second time in such split-second decision-making.

What if you could click down on the ability icon in the UI and drag it to the specific champ/target, and the next time you simply press the ability (When within range, of course), you use that ability on the certain target right then and there, simply with the push of one button?

It would help with champions who use dash/blink abilities (including flash) and have lock-on abilities as well.

Lee could buffer his ult on someone from a distance, then when he manages to W in behind that champ, he just simply taps R once and instantly kicks the target backwards.

Vayne could buffer her E on a support, and the second that support gets a bit frisky and possibly flashes in, Vayne could just tap E and knock that support away. Or she could do the Lee thing, except with a quick Flash E combo.

Yi could buffer his Q on any champ with some nasty CC, and the second they start casting it, he can just Q away.

The possibilities are endless!