I think we are getting off topic.
Look Mystaticromance I understand (as a career blm) that you want more inventory space and want to optimize your spells. However, There is no way in hell that SE would go for your idea... it is not because it is not inventive, but because simple put the resulting staff would be overpowered (as it should be if you are combining all of the endgame staffs) and god knows that we deserve something powerful after the joke that is empy-staff. It boils down to what this DEV team considers balance...
Now something as massive of your weapon idea might not be possible.. but what if there was a lvl 99 staff that was similar to the day/weather augmenting gear? or even one that would double the damage of an elemental magic critical proc?
We need to suggest things that are viable, as the DEV team will ignore most "far fetched" ideas, just look at our threads... how many responses from DEVs do we have? Like 3 ... Black Mage is sadly not a focus for the DEV team, something that I have sadly had to accept after playing sense NA release. Maybe one day we will get our super staff.. but until then the Magic Accuracy +10 "Magic Atk. Bonus" +50 of the Laevateinn (90) looks good to me!