It's good that there have been someone with Albert Schweitzer's character, or a planet like Saturn. When we talk of the value of there being a thing of a particular sort, we're talking of the value of some property being--say, being a ringed gas giant of such and such appearance--being instantiated. Intuitively, that value of instantiation resides in the instantiated thing: it seems clear that Albert Schweitzer and Saturn have the goods of instantiating Schweitzerlikeness or Saturnlikeness.
But there is a problem with this obvious thing to say. For if the value of Saturnlikeness being instantiated is found in Saturn, then if there were a second planet, Shmaturn, that was Saturnlike then we would have that good twice over, once in each planet. But that misunderstands how goods of instantiation work. It is good that Saturnlikeness be instantiated. It isn't twice as good that it be instantiated twice.
So what do goods of instantiation reside in? One could answer: "Nothing. Goods don't need to have a substrate as a home." But I do have the Aristotelian intuition that goods have something like a metaphysical home, that it is good that p only if that is a good for something that p. Maybe I should abandon that intuition. But let's see what we can say given that intuition.
If Platonism is true, then a very natural answer is that the goods of instantiation are goods for the instantiated properties. This leads to a very interesting idea. Artists do good to the Platonic realm by instantiating it. God benefited kangarooness by creating kangaroos. This seems a bit crazy.
If theism is true, then perhaps goods of instantiation are actually good for God (in a non-internal way that is compatible with divine aseity). God has something supra-Schweitzerlike or supra-Saturnlike about him. It is good for God--it glorifies him--for there to be something Schweitzerlike or Saturnlike. This approach may not actually be that different from the Platonist one if properties are divine ideas.