That's a great question and now that it's getting cooler, it's a REALLY timely question. I'd love to hear what others have to say, but whenever I wear my short black biker/cafe racer jacket, I do wear boots on occasion, either over my jeans or the short pointy ankle-height Guess ones.
Scarves always look amazing at the neckline and as for a bag, I change my purses and bags fairly often and rather like the use of color for contrast, even if it is also leather. Hope some of this helps.