Cedric and Bertrand want to see a movie. Bertrand wants to see Muscled Duded Blow Stuff Up. Cedric wants to see Quiet Remembrances: Time as Allegory. There's also Middlebrow Space Fantasy. They are rational but not selfish - they care about the other's happiness as much as their own. What should they see?
I personally think that something more akin to minimum utilitarianism is more inline with my intuitions. That is, to a first order approximation, define utility as (soft)min(U(a),U(b),U(c),U(d)...) where a,b,c,d... are the sentients in the universe. This utility function mostly captures my intuitions as long as we have reasonable control over everyone's outcomes, utilities are comparable, and the number of people involved isn't too crazy.