I think remaking the Hat was a terrible idea.  But I also think it's hard for some people to let go of what they consider tradition.  After becoming a teacher myself (after having written this story!) I can clearly see members of the community saying that they just can't *imagine* Hogwarts without its Houses, and hinting that they would stop supporting the school if the Hat were not re-made.  Slytherin parents would demand to know how they could be sure their child were associating with the 'right' people, Ravenclaws would ask pointed questions about the right kind of study environment, and Gryffindors would make dark comments about exposing their children to Dark Arts practitioners in training.  DDore probably wants to keep his eye on Slytherins, himself.  I see this as a wrong decision, but I understand how he could make it without being Made of Evil.

-K