If you are looking for shrubs: Willows (totally a hit! Short early spring bloom period but VERY popular), serviceberries (Amelanchier sp) beautiful spring blooms too.
Agastache was a hit with my bumbles this year...and then the goldfinches liked eating the seeds...
Fall ones I love are any of the asters and goldenrods...I'm trying a few new ones this year from plugs hopefully have lots of flowers next year. (had Calico, it was always covered with bees, but it spread way to much from the rhizomes, worse spreader than Canada Goldenrod by far! Beautiful little rascal...) In my butterfly observations the Monarchs always seem to be nectaring on New England Aster so thats always a nice one too, should be fairly "well behaved" and beautiful colour too.
