A lot of the necessary information is even readily available such as the list of creatures, the list of ingredients, the magnificent history rich with saga and tales. As a D&D Campaign, I could set the Aquaria storyline for the game as a sub-campaign as most of the races are gone. However were I to come up with a larger, grand scale storyline (which I would and have been thinking of for some time) all of her once races would stand tall and powerful. Perhaps with Alec and Derek's honorable presence, I might be able to come up with some other locations in the waters surrounding home waters, where the once temples stood, The Very entrance of the King Nautilus, the King Blaster and his swarms into home waters and how they were trapped into their perspective temples or caves and left to be, perhaps even becoming points during the campaign that would close off, and become secured by armed Guards lest they escape their watery cages, the schools of magic that are present in the game alongside the ones already present in D&D.
For Naija's story as an offshoot much of the old magic would be lost, few small remnants made divinely available to her (or the party) through the verse and the defeat of the Godlings perspectively.
Herbal arts, as much as they were a part of the game, should be a part of my ideas as well. However in the base campaign they would be imbued by magic and bolstered by skill.
In Naija's world, the Verse supplies much of the magic that is put into her recipes.