To me, Meats was borderline. Too many advantages without any significant disadvantages to go with them, but since he's not blatantly more powerful than a peak human like Bane (without venom) then I was willing to accept him. But back to Zakith.
He can shatter stone with little difficulty, and often overpowers opponents much larger than himself (300 pounds).
Is that referring to the weight he can lift, or the weight of the opponents he can overpower? In comic-dom, 500-600 pounds is usually considered peak human, though personally I'd put someone like Bane at around 1,000-1,200, and your guy strikes me as being similar to him.
I'd also prefer he not have any kind of plate armor (apart from maybe a pair of bracers), since this is supposed to be skill vs skill and Zakith isn't lacking even slightly in that department (if he was less skilled than the others, I'd be willing to allow armor to make up for the deficit, but he's clearly not).
One last thing is the speed with which you say he can wield his sword. Just keep in mind that a 7 and a half foot sword that weighs 23 pounds is most definitely going to move slower than my tomahawks or Green's katana, simply due to the restrictions of physics.