I've seen a metal rod embeded in the concrete sticking up into the bottom of the post, which was pre-drilled with a hole for this rod, but this requires careful planning or a larger hole than the rod, so that you can slide the post over a 1/4" if necessary.
I've also seen a black metal band put around the post and slid down half way over the same size concrete footing to hold it in place, like a collar, half over concrete-half over wood, so to speak. It looked good as it was painted high gloss black. And it secured the post to the concrete pad.
On other raisings I've seen just angle irons hooked to the concrete and then threw bolted to the bottom of the post. But I'm sure that's what you're trying to avoid.
Maybe others will post some of there observations or ideas.
Good luck, Jim