Originally Posted by
Holiday
I think you're underselling God Hand quite a lot. Absolute nullification of anything ranked B or below is no joke, especially considering that NPs are ranked on a more demanding scale than regular attacks (there's a statement in Stay Night that an NP with the same firepower as a rank A+ regular attack would only be rank C). You can take the roster from pretty much any HGW we've seen, and at least a third of the Servants will have literally no way of piercing God Hand (and most of the rest will only be able to pierce it with their strongest NP). This is even true of very min-maxed HGWs with lots of prep time like Zero. It says a lot that Siegfried only has the damage reduction component of God Hand (with the added demerit of his back being vulnerable!) and he was still considered one of the Black Faction's aces in Apocrypha.
And then, on top of that, you've got the resurrection component, which shore up the vulnerability Herk would otherwise have to instant-death attacks like Gáe Bolg or Zabaniya (assuming they could break through the rank nullification). Plenty of Servants rely on instant-death NPs to compensate for their weaknesses in other areas, and they just plain don't work against God Hand. Well, they "work", but only in the sense of "great, you just took off one life, now do that again eleven times before Herk kills you". And then, on top of that, you've got Herk's defense tripling every time he experiences an attack. It's probably the least impressive component of God Hand, but it's not nothing.
And, as Menwearpink pointed out, combining God Hand with the pelt has a cumulative effect. We've seen several times that Mind's Eye (Fake) basically amounts to "Herk can tell whenever an incoming attack can actually hurt him", meaning he never has to expend any effort on dodging or deflecting anything which isn't good enough to get past his defenses. And once you eliminate everything ranked B or below and everything man-made from the pool of attacks Herk has to bother defending against, the remaining number is so small that his high stats should be enough to keep him alive in all but a few highly exceptional circumstances. Yes, he still wouldn't win against Artoria Alter, but that's because Artoria is already a top Servant, and she's been supercharged with so much magical energy by the Grail that she can spam her most destructive NP with impunity. There are plenty of great Servants who would struggle against her.