Today: Progress!
Thanks again for your replies. Today Wesley and Stephen's replies suggesting that it might not be the hanger had me scratching my head in new and exciting ways. Thank you for your suggestions that I keep searching.
I remembered that back when all this began my friend Tess at A1A bike shop in St. Augustine asked if there was play in the freehub body or the cassette. I checked both and noticed a very small amount of wiggle in the cassette. It seemed acceptable. She recommended that I try a different wheel and cassette. I hadn't done this yet and decided today that I'd try a wheel swap before purchasing the Park DAG. I'll probably still get one ;)
This afternoon I removed the wheel, removed the S-Ride 7-speed cassette and installed an 8-speed cassette from my parts bin with the same cog configuration (11-32). Snugged it up, re-installed the wheel. It was raining out and I rode around the neighborhood in my jeans and wool Birkenstocks until my pants and shirt were soaked.
No skips from the chain! Until today all of my dozens of test rides resulted in the chain jumping after the first few strokes. I would ride the bike out of my shop and start saying, out loud, "Clunk clunk clunk." Then the chain would clunk and I'd say a string of words that would get me forever banned from this forum.
This time it didn't happen once. I rode for about two miles around the neighborhood in my smallest three cogs, pedaled hard, climbed a hill, pedaled out of the saddle. Chain felt and operated like normal. I'll have to take it on a longer ride tomorrow to be sure.
I believe the cassette lock ring was loose, introducing movement in the cassette. When I say the chain was "jumping" I mean that when I pedaled under load the chain would physically slip, clunk loudly and interrupt my stroke. I think the chain would slip off of one of the cassette teeth, slide for a second, then engage with another tooth. It makes a sharp, loud noise that sounds unpleasant and feels wrong under your feet.
The lock ring must have come loose during the fall and subsequent mangling of the derailer and hanger.
I wish I'd listened to Tess right out of the gate, I would have been much further along if I had. It would seem my hand and eye derailer alignment skills are passable.
I currently have a Deore XT derailer installed. I much prefer the classical looks of the Suntour Cyclone but I'm going to leave the XT installed for the shakeout period.
Thanks again to everyone for the help, encouragement, kind words and collective brainpower!