The official Dahl site has an interesting blog post about first-draft Charlie material that was later cut before publication. For example:
‘The Warming Candy Room’ [was] described as ‘like the engine room of a gigantic old-fashioned ship’, created red sweets that will ‘warm your entire body even on the coldest of days’
I also loved the idea of “enormous snow-white polar bears made out of white chocolate”!
There are photographs of Dahl’s original hand-written manuscripts as well. If you’re a Wonka fan, you should definitely check it out.