I read your announcement about the upcoming changes, but I think there is a much better option for these things. Let me show you with some pictures:
First Picture
So, If you buy a cosmetic item, you will be able to claim that on any of your character. No need to transfer trought storage, you buy the item account wide and also you can delete it accidently or just for fun, because you can claim it anytime, as much as you want!
If you buy it’s yours, you can use it. Deleted a character? No worries, you can just claim everything, since you already bought them.
Edit:
Cosmetic items are not in stock. They can be claimed as many times as you want, on as many characters as you have.
Basicly if you create a new character, all you have to do is claim it on it.
Second Picture
Are you unsure about your EXP Tomes or Skill reset potions? Worry not! When you buy it, it will only goes to your stock and you can claim it whenever you want on your prefered character, just when you need it!
That’s all! I think it would be much easier that way.

And can be used anytime on any character.
It costs time…but in the long run, it’s the better way.