I used 3/16 of an inch. I normally use 1/4 for swords, but because executioner swords don't have distal tapers (or any tapers), I went for a thinner blade.
I have not put it on a scale, so I can't tell you the exact weight. Just holding it in your hands, it feels as nimble as any other European longsword, but when you swing it, it feels like a cement pillar.
Yeah, I could see that, it's a beautiful piece and as an executioners sword it would be perfect for removing heads. But you would need arms like the Hulk to use it in a fight.