Zandra this is no way inventory -1 any good scholar with this saves around 7 inventory slots since you dont need individual elemental staves anymore and with storm spells its effective 100% of the time
This staff is still garbage, the -emnity is nice but the Magian staffs already give you a small edge even as a naked sch/rdm. Once you put on gear the difference grow even wider.
SE could easily fix it though by either subbing out the MAB bonus for a universal weather affinity of the corresponding value or adding a small value of it to the MAB bonus.