Thank you for your thoughts! We (dark_agenda), will discuss the matter re: canonically titles internally.

The reason I said it felt weird for the Madoka one is because the suggestion was not just to put a description but to create a fake Japanese-y fan name, which to me feels really...idk, presumptuous? Because to write it in Japanese like that is presenting it as if it's what Japanese fans use, when it's (to our knowledge) not.

That's a valid concern. For the nominated name of "Savanna magical girl", we'll likely use Saban'na kara no on'nanoko | サバンナからの女の子 | Girl from Savannah or a variation.

Do you have suggested translations for girl from Tibet and girl wearing a ḥijāb? For the nominated name of Tibetan magical girl, we might go with girl from Tibet or Tibet-chan | チベットちゃん as erinptah and you noted above: http://dic.pixiv.net/a/チベットちゃん