Yo, I'm Jonny, your friendly neighborhood furry, and today, I've come to give my two cents regarding the expansion of existent magic and the creation of user-interpreted pages.
I'm going to cut straight to the point here, under no circumstance, will there ever be a need to create a whole-new version of an already-existing magic. Canon content is by-no-means limited and is being expanded on by the admins as we speak, and concepts produced by other members of the wiki can be utilised without much hassle through acquiring permission from the respective owner of the concept.
Sure, we've all done it before, or at the least thought about it, but what benefit are you gaining when erecting a page for your adaptation aside from renaming the page (though most of the time "renaming" is simply adding your name or the word "magic" at the end) and sticking your template on it? Unless feeding your ego happens to be one of your pastimes, you gain nothing.
Here are some common thoughts that occur when expanding on an existent magic and solutions that don't involve creating a page;
1) "I want to add some individual flair to the magic." Then look no further than your character pages. Magic, no matter how basic or common, should always be unique to the one casting it, this provides a great opportunity to add your own twist or interpretation of the magic at hand.
2) "I want to expand on a certain aspect of the magic." Go ahead, as long as it falls within the boundaries of what's capable with the magic, though it's still not a sufficient reason to increase the overall page count of the wiki. Though if your expansion deviates considerably from its originator, then you're better off making a new (subtype) magic entirely or consulting a fellow author for their opinion, rather than senselessly making: "Wood Magic (FurryBoi)" or "Earth-Make Magic".
3) "I want to reword the main page's description slightly, claim it as my own while also adding nothing remotely substantial when compared to the content that is present." Look, you're not fooling anyone here, if anything, you're making a fool of yourself. The description on the page you're referencing from, detailed or lacking in detail, is never final unless explicitly stated so. What does this mean? You can write your own (logical) description and you won't be attacked for writing it, so I encourage you to do just that, not only will it boost how confident you are in your writing abilities, it'll make your articles a heck of a lot more interesting to read.
In summary, your interpretation should ideally be projected onto your character pages, instead of warranting its own page. That's all for now folks, and don't hesitate to leave your own opinion on the matter on my talk page, Discord, or down below.
Jonny (HERE'S JONNY!)