[Shadbase]

If nothing else, a button on the login screen (or even just a command only accessible there) that orders all characters on that key to en-masse send all donation items (and donation currency) to the global bank and log what those items were would be a major boon to the problem, meaning you only have to log into a single character to grab anything you need, and wouldn't be too potentially weird to introduce unto the game's loading screen.
We already have something similar if we delete a character, so surely the possibility of that is favorable?