All excellent advice. If you take the route of asking the AHJ, learn several approaches first so that you can tell him that you know of several ways to do it but would like to know from him a)what he prefers and b)if there is a less expensive but acceptable way to do it.

The AHJ will feel like you're listning to him, putting you on a better footing with him on all aspects of what he has to inspect, and he might come up with an idea we haven't thought of.

bcf, around here, all islands worth doing have sinks in them, so, there's plumbing, so, these can't be pieces of furniture unless there's a floor sink (as in restaurants to allow reconfiguration). Come to think of it, though, cgav didn't mention this, and it's much harder to get plumbing to the middle of the floor in a slab than to get electrical there.