For weeks a small leafcutter bee species has LOVED my veronica blooms...and also used the leaves to cut discs for nesting. I LOVE leafcutters.
Most of the herbs...if allowed to flower, may not look like much but tend to be huge pollinator magnets.
Most people plant for mid season. More focus needs to be on really early flowering and late flowering plants.
You would be surprised at how much pollinators use holly blooms...and they are pretty early.
Monardas...hummingbirds and bees! Great plants.
Black-eyed susans are great for long flowering period and attractiveness to pollinators.