The potentilla will not be happy in that low a light condition with very little flowering plus it looks pretty much like a collection of dead sticks throughout the winter. And I'd not select a physocarpus just for winter interest - while they are a great plant, I don't find them to be particularly outstanding in winter. It's the foliage and flowers that are their greatest attraction and you'll likely miss a lot of that effect as well in no direct sunlight.

If by dogwoods you mean one of the selections of twig dogwoods, those would be high on my list of possibilities. They are extremely hardy and very shade tolerant. A variegated form, like Cornus alba 'Ivory Halo', would brighten this area considerably during the growing season and offer bright red stem color during the winter months. There are a number of other possible cultivars you could choose from as well, some that offer bright gold or even orange stems and with a variety of variegated foliage.

Thank you!

I thought I'd posted a reply yesterday--oh well.

I had been thinking of either an Isanti or Ivory Halo for the left side--and I like things to be sort of matched--so I like the idea of planting one on the right, too. I'm excited to think it may be fine, there!

Perhaps the Isanti on the left and IH on the right?
Thanks again.