I just had to try my luck at my tree crystal castle idea. I’m not very experienced with architecture or interiors, but anything would be an improvement over the castle’s current look. I don’t enjoy the canon design at all. Not only does it exist for the sole sake of merchandizing, but it’s more out of place than a sickle and star at a Nuremberg rally: it doesn’t blend with Ponyville’s rustic charm. The interior with it’s jagged purple/blue crystals and tall, slender green windows feels cold, dark, and more befitting an evil queen than the princess of friendship. And besides, we’ve already got an entire empire made of crystal (I can already hear Herr Strider growling “It’s a city state, not an empire!”) we don’t need another crystal structure. You could argue that the castle’s colour scheme and rigid shapes were chosen with Twilight’s design/personality in mind, but that still doesn’t do it for me. If it’s a castle of friendship, shouldn’t it have warmer, more welcoming colours? Shouldn’t it compliment all of the mane 6’s personalities? Also, good luck getting a purple unicorn to stand out against a purple and blue backdrop.

In my headcanon the Tree of Harmony replaces Twilight’s destroyed library with a giant half-wood only-partially-crystal tree castle, I think it sits someplace behind where the canon one is now, that way half of its root system lay in the water - that fountain has to have some kind of source, and since we’re dealing with natural wood we know it isn’t piped in. Plus I don’t think we’ve seen a castle with a waterside view in the show, that’d help it stand out. Instead of a Twilight-centered interior design, the treecastle has elements that compliment each of the Mane 6: an awesome skylight, regal curtains, rustic cushions, tranquil foliage, and confetti cannons. Hidden ones. Plus it’s so similar to the library Twilight won’t feel restless and we can just skip the twenty-two minute padding– I mean… “slice of life” episode that is Castle Sweet Castle.

I bet it’ll grow new/bigger rooms as the centuries roll by. I think by the time Twilight has taken Celestia’s place and is grooming a future-alicorn student of her own, we’ll be dealing with Yggdrasil levels.