Not really sure what you have in mind but I'm totally with you about the hotbar management.
It's actually very very boring and we have to spend way too much time to manage them.
They definitely need to work on that and something like a popup / Pillars of Eternity / Baldur's Gate things should work well.
What I had in mind was something akin to the Throw ability button, or when you use the Hex spell. Just click the button and the available spells/items show up. One button per available spell level, and one for scrolls, potions, arrows, etc.
Make it similar to the buttons on the left side of the character portrait.
Having some quick access buttons is nice though, as there are some spells/items you use a lot, after all.
