LOL! Such a dilemma. The real answer, of course, is to wait on necessity or an irresistible urge or an incredible sale (the last is what usually gets me). But since you ask....
Go with the Aura One. It's got a bigger screen and it will give you different functionality than Kindles, as you're still happy with your Voyage anyway.
(Pay no attention to the devices under my avatar!
)