A beam around the edge of the lower slab is a great idea, as the beam will automatically show as hidden (depending on the Model View Option Settings).
The down side is the beams are not associated to the slab, so if you have to edit the slab size/shape, you have to edit the beams as well - that is not hard.
Taking it one step further then, would be to use a slab accessory - which we have if you installed the goodies.
The downside here is you will need to create an add-on object that can add the splayed edge, and if you want to be fancy, make it so the angle of the splay is adjustable.
There is nothing out of the box that I know of that can do this.
There is an accessory that can add a footing to a slab, but it is not adjustable to allow for just a splayed edge.
I am on eave in a couple of weeks, so I might be able to whip one up as a Christmas/New Year present.
But not before then unless I find some spare time.
One of the forum moderators.
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