Whould it be possable to have a key to organice stuff in backpack, a key for storing all spellbooks for instance.
There exists a script for a Spellbook/Runebook key. Unfortunately it is terribly buggy and causes server issues. So it is unlikely to be implemented.
How about the spell book basket like what is used on paradise found server ? They also have a rune thing can't remember the name but it held like 500 runes or something crazy like that.