Haha wow, that armor looks really badass! Are you planning on soloing the next difficulties as well? I heard NM was a real pain for Barbs. But nice job man!
I am for the most part soloing nightmare, but it is rather difficult. I try to play online when I can, but its hard to get good groups and none of my friends are every the same level/difficulty as me.
Norm is a cakewalk, I play a 60 dh at the end of act I inferno soloing. You will most likely need a partner for bosses in act 3/4 for hell.