I am not saying you're bad for using a witches hat by any means. I mean if you made it work for you that's totally awesome. However I think you can make a perfectly descent cosplay with out using one too. I've cosplayed Kuronue a couple of times and both times I never used a witches hat.

I used a visor, glued some cardboard on it, shaped it, then covered it with leather. The buckle was gold painted femo and the strip was grey cloth. I've been told by many people told me as well that my hat looked just like Kuronue's and they were very impressed.
If you ever get around to taking a picture of just your hat and posting it, I would love to see it ^_^. I'd love to see what you did to make it work so well. With so many other cosplayers I have seen that use a witches hat for their Kuronue cosplay it looks just terrible, they just don't know how to cut it, or don't bother cutting it at all
gonk They completely insult the wonderfulness that is Kuronue's hat.