But the question at hand is: which things are good and which are bad? Is one happy and one unhappy person better or worse than two persons going "meh"? Is one person being tortured better or worse than a large number of people suffering dustspecks?

Depends how happy and unhappy, and how much torture vs. how many dustspecks.

One set of answers is only objectively more or less rational according to a particular utility function, and we can only do our best to work out what our utility functions actually are. So I certainly can't say "everyone having $900,000 is objectively better according to all utility functions than 99% of people having $1,000,000 and everyone else having $1," but I can say objectively "this model describes a utility function in which it's better for 99% of people to have $1,000,000 than for everyone to have $900,000." And I can also objectively say "this model doesn't accurately describe the utility function of normal human beings."