Amaterasu has pretty much everything beat. It doesn't even make sense why Sasuke didn't eat another one in his fight with Itachi.
Sasuke: You think that you're hot stuff with your instantaneous unavoidable instakill instagib attack Itachi? Well, I have an ultra unavoidable instakill instagib attack that -doesn't use any chakra or have any downsides and just requires rainy weather or fire jutsu to be used repeatedly-.
Itachi: Indeed, Sasuke, that is some impressive haxxoring of the Naruto universe. You are a true Uchiha. But, you -are- out of chakra so you can't do your instakill instadodge kawarimi! So, without further ado, Amaterasu!
(90% of Sasuke's body bursts into flames which is instagib instakill and then Itachi plucks out Sasuke's eyes from the smoldering remains.)
Or even more realistic, Itachi just makes Sasuke burst into superflames during the middle of Sasuke's soliloquy.
Failing that.... Itachi has an invulnerable chakra robot with a... well you know the rest.
Some people might say that Itachi didn't have enough chakra to use Amaterasu again, but for some reason I think the chakra robot uses more chakra. I call BS.
As for dodging Amaterasu, Sasuke didn't dodge Amaterasu. You can't dodge it, which is stated. Itachi turned it off because he didn't want Sasuke's eyes to burn, which is plot no jutsu. Apparently, Sasuke also has an instadodge kawarimi that is immune to instakill, but he can only use it once. So, you always have to kill Sasuke at least twice. However, Itachi can Amaterasu you until he goes blind or runs out of chakra or gets super Mangekyou. He can Amaterasu Sasuke more times than Sasuke can instadodge.
As for Minato, Hiraishin does constitute an Uchiha level instakill under the right conditions. But what the heck, maybe Itachi will pull out another sharingan based ultra mega ability. I mean he pulls out an invulnerable chakra robot with an instakill one-hit attack that ruins people that are immune to death itself. How is that even an eye technique? He's an Uchiha; apparently, that means he can do whatever he wants.
But keep this in mind, Minato would have to touch Itachi with a seal or set a trap to instakill Itachi --- and sharingan sees chakra. As for surprise instakill, Itachi has the superior surprise instakill. Itachi could just sit on roof or maybe fly, because he's an Uchiha, and just look at Minato from a hidden location. -Surprise instagib instakilled-. Minato is giving a speech about how Konoha is going to enter a new age of prosperity then Minato spontaneously bursts into unavoidable unquenchable superflames in mid sentence. Essentially, the best logical defense against Amaterasu is to never be visible, anywhere or anytime. Hiraishin has incredible utility (you can teleport across the world in a second, anywhere you are needed) and can be combined with rudimentary kunai for an instakill, but it is not instakill on the same level as Amaterasu.
It's not that Minato is weak. It's that the big three Mangekyou techniques are totally wtf. Tsukuyomi was unbelievably powerful, but Amaterasu is just a visual wish for someone in Itachi's sight to die in a horrible way. --It's not about how fast Minato is; it's about if he is ever visible anywhere or anytime.-- If that doesn't work, then Itachi has an invulnerable chakra robot that instagibs everything, even things that can't normally be killed.
I've heard people mention that the First Hokage had some “Bringer of Darkness” technique that shut out vision. If that's true, then it's possible then only the First Hokage (or somebody with a similar technique) can take on Amaterasu, if he isn't surprise instakilled and you have arena rules. Essentially, you'd have to get the Uchiha to play nice and have a non-genjutsu technique that permanently blocks out their vision, which the sharingan can't copy or counter.
