Love it! But I think you should not do up the bottom button. It needs to flare out behind you when you walk. Also, as a petite, undoing the last button or two draws the eye upward and balances your slim hips. (I know this because I've got similar issues!).
If it were my coat I'd wear it all the time. Who doesn't want to feel like Sherlock? But I'd probably wear it only with a chunky heel. Longer coats make me feel stumpy for the same reason that longer skirts do, so I need a bit of a heel to compensate. But I think you could probably get away with it with those buckled boots.