We grow in virtue by delighting in the good, and we express our freedom most fully in doing what the good thing to do is.
Sorry to intrude with a non-comment comment, but I couldn't find a better way to ask. When I click on the highlighted word "liberty" in this post, I am taken to a confusing page:
Is this supposed to work this way?
I'm not huge on Kant either, but I agree with your sentiment about being fond of his love of duty. Perhaps a way we could reconcile him with Aquinas (though, in truth, it might be Aquinas making this point more than Kant), is by saying that virtue is a duty, but that we are meant to find doing our duty joyful as well, since duty is a good thing. Kant would say that a chief characteristic of duty is that you do it even when you don't want to...but Aquinas would likely say something closer to, "You should want to do good not only because you love good things, but because they are your duty, and you ALSO love doing your duty." I do think, obviously, that duty sometimes involves doing things we'd rather not do...but we can cultivate a love for duty as well, to make doing our duty easier.
“England expects that every man will do his duty”
I have ranted before about how our modern anti-culture is so hostile to duty that it can’t even comprehend the idea, so that for instance the entire genre of duty-before-self-gratification movies are impossible to imagine today (think Roman Holiday, Prisoner of Zenda, even Casablanca). It was nice while it lasted..