The listing so far is Time, Space, Gravity, Life, Death, Chaos, Fate, Light, Dark, Twilight, Shadow, Quiet, Insomnia, Unexplained Noises, (Sweet) Dreams, Sleep, Winter/Snow Mister, Summer/Heat Miser, Fall, Spring, Wind, Ocean. The Earth itself and the Sun also have their roles, especially as they could technically be considered parents? But it's pretty far off and removed, and they might not communicate quite so readily as the others do. Some esoteric hoodoo in how they operate.

Still thinking over Gravity, this might tie more back into the Earth given that, well, Earth is the one that's making Gravity be a thing. Maybe he/she/they are the oldest of the lot, and everyone kinda happened afterwards? Still feel like there would be some relation to Time and Space, as all seem fairly intertwined. Triplets?

All of the entities work off of a sort of 'two extremes' dynamic, even the Night Entities themselves. Dreams is really the only one without a direct counterpart. For the others, it's Insomnia/Sleep and Quiet/Unexplained Noises. Might sort of hint at the powers of the mind? Been watching Hunter The Parenting which is based in the World of Darkness lore, which has an esoteric plane called the Umbra that contains all kinds of fun afterlifes/creatures/entities. A similar plane being where Dreams, and another entity that becomes very important later, ties back to? Weird kind of 'your mind makes it real' rules.

Related to above, the idea of the mind being important also ties back to Rise of the Guardians/Guardians of Childhood rules (also present in this AU pileup), namely the Clap Your Hands If You Believe trope. Belief and the mind are important. It personifies and it empowers. Multiple gods, goddesses, and demiurges are present in this world as a result, though they all tie back to human interpretation and belief. But the Ancients, those are the oldest of the old, made out of the sheer certainty that the first life to crawl from the Earth had, that This Is The World And These Are The Rules. This Is Reality, And This Is How Reality Behaves.

As such, many of those First enjoy a pretty good position as far as standing with the other pantheons. Sweet Dreams actually being on great terms with some of her younger counterparts like Morpheus (Greek), Tutu (Egyptian), and Yohualticetl (Aztec). Sleep and Hypnos occasionally getting together for drinks. Dark has...a bit more of a tenuous relationship with other entities of darkness just because many of them are...a bit more wild than he is? Not that Dark doesn't know how to have a good time, he's just a little bit less crazy about Things That Go Bump In The Night. Especially after he comes to empathize with and like humans more. Light actually enjoys talking to Helios and Amaterasu, and yes he did get clotheslined by Maui that one time but it's cool, they're cool now.

Death solely covers the moment when a life stops being alive, not everything after. He is not a psychopomp guiding people to the afterlife, he's just cutting their connection to life. Other entities take on that role, especially across cultures. He's also aware he gets a bad rap, though he's a bit more patient with it and less depressed. He gets it; living things have a vested interest in staying alive. What rankles him more is the sanitization and lack of discussion around death, to the point where people will say something like 'un-alive'. It definitely says a lot about how people view you when they will use an antonym to do it.

Time is a bit of a persnickety bastard and it does annoy people periodically (Especially Death sometimes, who has to deal with him a good amount), but a large part of this is because people keep messing with his work to varying degrees. Magic is present, so people enjoy going back and changing things and Time gets very annoyed by it because the Butterfly Effect is absolutely a thing when it comes to his work. Yes, he's aware the Titanic was a tragedy and a lot of people died horrible deaths, but because of that, there are more stringent rules and regulations regarding ships so things like that don't happen again. Sometimes the bad thing needs to happen to teach a very important lesson, and taking it away means that the lesson is never learned. Also, hindsight is 20/20, sometimes you don't see the effects of things until years down the road. Getting too fixated on what happened before just draws you away from the Now. If Time has one lesson he wants folks to learn, it's live in the present and LET ME DO MY JOB IN PEACE.

Time will get tetchy if you start looking back and forward through time (See Project Looking Glass). Though ultimately that's relatively okay, so long as you're not physically heading back or forward, or trying to change anything. Time gets the curiosity, after all, there's only so much you can gather simply through speculation, and humans love to know things for sure. Asking a nonhuman also can be dicey - who knows what they'd want in return, or if they're telling the truth? They also might simply not know what it is you're looking for. Omnipotence is a thing only few have, for better or for worse.

Fall and Spring being Snow and Heat Miser's chiller sisters, carries on a trend with the 'in-betweens' or transitionary entities having a bit more flexibility to them as far as character and perspective.

Wind and Ocean being Present but not always 'aware'. Maybe they can sense what happens in a particular area, focus on a particular part of their domain, but it'd be overwhelming to try to take it all in. They do have avatar forms, but only sometimes use them. Everyone generally gets along with them, they're hardly difficult to get along with. Might notably not take sides with different sibling rivalries though, albeit some might say this is for the best.

Compared to Time, Space is a much more calm, 'spacey' personality. Can freely teleport (see Paradox's powers in Ben 10 Alien Force). Admittedly, this personality can make him clash with Time, there being a few incidents where Space is forced to draw off so his brother (hopefully) cools down. Doesn't make him feel fantastic, though, especially since Time definitely has his opinions of more 'lackadaisical' personalities.