I like enchantment for the Fairies, if anywhere. maybe the vegetation, too, if they are connected. I imagine the nights on the plane to be very
Starry Night.
Not hot on dominion/status/prestige. It's backwards and doesn't really support
any theme well, because they could belong to any. How many
Arctic Avens do you even want in your set? You usually have a few cards like that anyway and it just makes this feel like an evergreen, except it wouldn't be evergreen because the freedom to just alter the bonus to e. g. +1/+0 and haste every now and then is more valuable etc.
I like the idea of using Aura tokens over counters though I'd conversely would have suggested ability counters at least for flying. It could be a neat trick to play with the amount of flying in the set if it is achieved e. g. through "renown - flying". Anyway, if we want to use Aura tokens, we probably want to create a keyword action that allows us to skimp on the full wording that usually requires (due to mandatory "with enchant creature" and "enchanted creature gets +1/+1") e. g. "When ~ enters the battlefield, infuse target creature with a white +1/+1 Aura."
One thought I had was to look at mounts again for spider-riding and drake-riding and flying seahorse-riding etc. Maybe not keyworded on just a cycle . I'd model it after crew: "Tap an untapped creature you control with power 2 or less: ~ gets +2/+2 until end of turn. Activate only once per turn."
Another thought inspired by the "red and shouldn't have enchantment creatures because our red people have other mentality", I thought about maybe having some different focus in Auras for the colors e. g. white-blue would have enchant artifacts, green-white more enchant enchantments, red-green could enchant creatures, and so on. somewhere there could be Curses. Having looked over the enchantment types we might want to return, that's an interesting one.
Sagas are basically deciduous, though funnily enough I don't feel the creative side of the plane particularly calls for them, though we could always use them to tell the current events e. g. "Dragon's Raid" or "<Planeswalker name>'s Stand/Rise/Fall" etc.
An early idea I had was to try and check whether we can actually represent the idea of floating/drifting lands mechanically e. g. lands that enter with flying counters that can be past on to creatures.
Being a top-down set we might want to just start with a list of things that we think really should be represented in the cards and maybe we'll find mechanical space to keyword that way.