Basically what the title says.

A lot of high quality things in general in this game are barred behind RNG, which is understandable, but can be very frustrating. Obviously, essences should remain relatively hard to obtain, but it would be nice to be able to know that you'll definitely be able to get X essence after Y nurtures, even if you get unlucky.

Unlike filtering by species, it also won't deprive less popular species of nurtures. It might even give them a boost, because people would be less worried about missing out on essences of species they actually want.

If I get something like this again, I'd like to be able to at least spend the 31k on some essences as consolation :P