Cho gath changes off point
Cho gath's issue is, he is HARD countered by mobility. They should just revert the w change. I think cho is fine against Champs that can be effected by more than his ult. If Cho gets infinite stacks a fed Cho will snowball ridiculously. Tank or AP Cho is useless while someone mitigates most of his kit, buffing him through his stacks would make an attack speed bruiser build the only way to build him.
What is currently on the pbe wouldn't help Cho, there's no way you can ult minions or mosters with a full cd. Increased hp later won't be so good, because its hard to be tanky late game. It would also be more annoying to ult someone to < 50 hp when killing with it is the only way to stack.
If they don't revert the w change they could atleast reduce it's mana cost.