not sure if this solution is what you're looking for, but thought i let you know anyway.

smoothing rounds your model from the lines closest to the hard edges of your model (see red lines). if you move these line closer to the egde, your bevel gets smaller (and thus your egde harder). you could also use split polygon to draw new lines closer to your edges. this method helps you in achieving a combination of different sizes of bevels and roundings in your model.

good luck!