Divine might be a little broad for me. I wouldn't mind segregating out the farsensing/info gathering spells and the space/time being spells into their own category.
There are two reasons for why space-time includes both divination and teleportation.
One is conceptual. When a person teleports to somewhere else in space (or time), the person is making some kind of link to that location, thus defacto using divination in the sense of remote presence.
Two is utilitarian. Divination spells are too passive, unexciting, and not really good spells because they depend almost entirely on DM whim. If the DM needs the party to know something, the party will learn it by whatever means. If a DM needs the part to not know something, even divination will fail to learn it. If the divination spell learns anything, it either doesnt matter in the first place, or the DM is feeling generous.
Oppositely, the teleportation spells tend to be a one-trick pony.
Nevertheless, together, the space-time thematic concept along with the active and passive utility, plus a satisfying repertoire of specific spells, creates a solid theme.
Likewise, I might break up Animal into beast and nature spirit spells and body affecting spells. Venom/corruption could also be its own category.
Acid can go anywhere: Fire, Water, Earth, Plant, Animal. Even Force in the sense of disintegration.
Similarly, Poison, but animal venom works flavorfully enough.
Separating Animal between animal body versus animal spirit, invites "summoning" in the sense of conjuring a virtual body as a separate theme, which could include other planars as well.
Obviously, perfect parity is impossible, but Plant and Illusion feel like the right "size" for a targeted spell list.
Yeah, each theme should have appealing spells to choose from at each level. For example, Plant simply stops at slot 6. There are no Plant spells at 7, 8, or 9. Each theme should ideally have at least three excellent spells at each slot. But the solution is to add more spells, or perhaps tweak one of the existing spells.
