I think having it configurable would serve 2 purposes that I think are important:

• Some more realism. Buckets made out of Bamboo shouldn't be able to pick up Acid or Lava, right?
• Another tool for modpack creators.

I am not sure how hard this would be to implement, but I think we should keep it in mind.

I can disable lava and acid easy, I just left them in for no other reason than the buckets were a pain to port and I couldn't remember is we allowed it or not - lol