People don't want other cards because we need them, but just because "other" is considered this mystical 13th element by many.
Cards that can use an quanta to power them are hard to balance and take away from cards that rely on elemental quanta to be powered.
I like that only some select, simple weapons and the shards are in other. I could see a few more other type cards like maybe a very plain spear. Maybe in the future with more quests/cards there will be room for more "other" cards. If they could have a use, things like empty pots, scrolls of paper, rocks, firewood etc could be introduced as other as long as they were not magical.
Anyhow I don't want other to be the 13th element, because it is not and shouldn't be. It just adds a few acceptable items that can be slightly useful occasionally.