Some Suggested Tweaks to the Galio Rework b/c I'm a Picky Little Boy
Mostly I like it, but there are a few mechanics that I feel lower the overall polish of his kit. Namely his two passives.
His PASSIVE passive gives him an aoe auto attack every so often. You can reduce the cooldown on the aa by hitting enemy champions with your spells. It works like Lissandra's passive in a way, and I dislike the way Lissandra's passive works. In a fight I find it becomes an unreliable effect that awkwardly comes off cooldown, often without me noticing, and doesn't really change the way I play anyway. I fear Galio's new passive will be the same. You'll likely be weaving in auto attacks anyways and a few of them will inconsistently be aoe. I just don't imagine feeling good about, or paying attention to this passive while fighting.
His W's passive grants him a magic shield after not taking damage for a while. It's kinda like Malphite's passive, but more specialized. This one's a little less convoluted to explain. I simply don't think a tank should benefit mechanically from avoiding taking damage. That's part of your role as a tank, and this mechanic punishes you for it. Riot said in their description that Galio is the kind of champ that goes in and stays in. If that's the case, this'll only effect him at the beginning of the fight, which makes him more engage focused, but also makes me kinda sad. He's an anti-magic behemoth, I'd kinda like to see that magic shield be more present.
So here's what my whiny ass suggests.
Passive Shield of Durand
Casting an ability enchants Galio for 2.25 second, with subsequent casts refreshing the duration. Taking damage equal 15% of your max while enchanted grants a magic shield blocking x damage and lasting up to 3 seconds. Galio cannot regain enchantment for a few seconds after the shield breaks. If enchantment wears off without granting a shield, Galio can't be enchanted again for twice as long.
Galio's rewarded for soaking up damage by being able to soak up more. Spacing out abilities grants more potential to shield, but maintaining enchantment to guarantee a shield might be better, as the enemy team can ignore you for a moment to reduce your tankiness throughout the fight. Using your W taunt can help trigger your shield, as you'll likely be more vulnerable to auto attacks than magic damage since you're building MR.
I also personally think Galio's Q and E should be switched. Q abilities have a reputation for being the bread and butter, favouring simplicity. Winds of War has a simple purpose, but it's delivered in such a unique way that I just don't see it being a Q like a simple charge and CC ability.
Speaking of which, when I watched the gameplay teaser, his E was showcased, followed by his Passive on Katarina. I thought it was all the same ability. I was thinking it was a knock up and then a slam down for aoe damage. Since I'm suggesting shifting his passive around, I'd also suggest reintroducing some aoe power by adding that functionality of the beat down for aoe damage after the knock up to his E.
That's all that I would say I dislike about Galio's VGU. I love the way he looks, and his CC heavy kit. His new ultimate looks badass. Only his passives and Q and E placement were off to me.