Your garden plans are admirable and appealing, Carol. You've given the design a great deal of thought, choosing plants that are good for your environment, as well as for pollinators.
I, too, love Coneflowers and Asters, but haven't grown any. I have a large patch of Thyrallis in my small garden. It only grows in zones 9-11, though - we are in zone 9 - and it attracts scads of bees and butterflies. Best part, it is a very self-sufficient plant, requiring almost no care.