"I disagree" might be split into subcategories (e.g. "fallacious") to not leave people guessing, like I've been left when I've received mystery downvotes. But on thinking about it, posts that get downvoted for wrongess don't generally have a single reason for it, and downvotes might be categorized falsely if there's some social reason.

So I revise my earlier prognostication - mo' categories is maybe not mo' better.