Possibly Monarda(Bee Balm), Symphyotrichum (Aster), Coreopsis

Rudbeckia fulgida, echinacea pallida, monarda didyma, phyostegia virginiana

I agree with all that were mentioned above. Also, Lupine, Monarda fistulosa, M. citriodora, M. punctata, Verbena hastata or V. stricta, various penstemon, Anise hyssop.

Of course that Rhody on the left is taking up about 1/3rd of the garden space. It is a beautiful specimen but may be better suited somewhere else, thus giving more room for natives, pollinators, etc.

Some of the smaller Echinacea cultivars would be good in there, also coreopsis., etc. Check the Prairie Moon Cultural catalog for interesting ideas growing natives.

Another option is doing the "Chelsea chop" to delay blooming for appropriate plants. My deer and bunnies have been doing it for me and I've discovered that Phlox paniculata and Lobelia cardinalis take well to such treatment by increasing the number of blooms significantly! You can leave a few unpruned and then prune a few others to extend the bloom time.