It would be a good addition to include total gold (currency) to be displayed on all characters. With warbands and cross faction being a feature in the game for some time now, it is no longer necessary to separate currency based on faction.

I would suggest adding a way for players to choose which characters they want to show up on the tooltip as well. That way people can control the list from getting too long in the tooltip. I wouldn't want the 20 unplayed characters to show up on the list to reduce clutter in the currency tooltip.