Galio's Ultimate

I've been playing Galio on and off for a few months now, and I've found that Galio's ultimate can completely turn around almost any fight. It does decent damage, and can lock down the entire enemy team for ages.

That is, if your ult doesn't get canceled because somebody clicked on you at the absolute last second before lockdown.

As Galio, I've had my ult cancelled "last second" in pretty much every way I can imagine (Thresh Flays, Yasuo tornadoes, Azir Ults, even Fiddlesticks fears). The problem is, even most instant CC effects are not quite instant. There is almost always a short, uncancellable animation, and as such an infinitesimal delay, between when the ability is activated and when the CC is applied. This means that your ultimate, which you usually have to wade through mountains of CC to use, ends up being cancelled before it has even begun. And if you try and wait for the enemy team to use up their CC, you end up losing the fight because they killed your entire team while you waited for a clear opening.

So, I would like to see all cast time removed from his ultimate (If it has one. I can never quite tell if the taunt is instant or if there's a small delay) and Galio made immune to crowd control from enemies affected by his ultimate's taunt. Obviously, enemies outside of his ult should still be able to run in and cancel it, but it's awfully frustrating to have your ult canceled by people who are supposed to be disabled

Speaking of which, there are several on-hit CC effects that, as frustrating as they are, I wouldn't mind still being able to affect Galio during his ultimate. I do think that his ultimate should make him immune to them, as a smart Udyr could just stay in bear stance every time Galio's around, or a Garen could just activate his Q and wait, but it's certainly easier to watch for Blitz's power fist than a Fiddlesticks fear (Really. A Fiddlesticks Fear. I mean, come on).

There are also some abilities, like Morgana's ultimate, that have a very clear warning before they CC is applied. These I am completely fine with being able to affect Galio during his ult because you can anticipate them. True, you can anticipate any CC to an extent, but, with Galio, it really only comes down to who happened to press the button first.

Any thoughts?