Well he's certinaly irritated "Ahhhh" ,and true for the rest.Sorry bro xd
It shows his DF mastery. Akainu's such a G, even haki slashes don't faze him. If it affected him in any way the panel would've shown an "ouch" or "that hurt" or a sound effect of getting hurt.
I know he could've destroyed the island, but like I said, slower reflexes play a part bro. He was essentially a walking meat grinder. He could grind anything in his path, but with that slow reaction speed anyone could avoid him. Anyone worth his salt that is.