It would help to know where you are located.

Ah! Of course. Washington DC sorry, USDA zone 7a

Honeysuckle is a favorite for hummingbirds. These two can grow upward on a support or left to grow as a large shrub.

Photo on the right (above) probably isn't correct. The true gold-flame honeysuckle (Lonicera x heckrottii) produces leaves that are paired at the stem ends, yellow flowers heavily flushed purple.

And the real L. x heckrottii 'Gold Flame' - with the two words used as a cultivar name instead of a common name, in order to distinguish a particular selection - displays deep green leaves and comparatively short heads of noticeably bright yellow flowers. I suspect at least some of these pictures show the right one (there's a number of different climbing honeysuckles all having the same general theme of pink, purple or red buds opening with contrasting coloring involving white, yellow or orange):

https://www.bing.com/images/search?q=lonicera+heckrottii+goldflame&qpvt=lonicera+heckrottii+goldflame&FORM=IARRSM

In a small area, I would use annuals that will bloom continuously through the warm season. Zinnias, salvias, verbena boniarensis, tropical milkweed, etc. I prefer to use native perennials, but they have a limited bloom time. A mixture of annuals and perennials could work.

Martha

Lonicera sempervirens ‘Major Wheeler’ is a native honeysuckle that blooms from June until frost in my garden, with a large flush of bloom early, but continued bloom on new growth all summer and into the fall and is regularly visited by hummingbirds.

Other plants liked by hummers and other pollinators in my garden include red single hollyhocks, pink-flowered coral bells/Heuchera, columbine/Aquilegia canadensis, Cardinal flower/Lobelia cardinalis, zinnias, scarlet runner bean, Salvia guaranitica 'Black and Blue' (favored above all my other Salvias), tall Phlox, Kniphofia AKA red hot poker plant or torch lily, Delphinium, and Monkshood/Actonitum (toxic to us but not to hummers.)

Thanks! Any of these survive in containers?

In my list, in your zone they are all hardy enough and should be fine in containers except perhaps the honeysuckle, which would need a truly giant container such as a 50 gallon trash barrel. You don’t have any available soil at all? I have only grown Salvia Black and Blue in containers since it isn’t hardy here.

I wouldn't feel too bad about losing the mimosa. They are not native, and they are invasive in some areas. You could just replace it with a beautiful native tree that has flowers for pollinators and leaves for caterpillars like a tulip or fringe tree.

Not a tulip tree in a small yard! But might you convince your neighbors to replant a large shrub limbed up to tree form as a replacement, especially if you shared the cost?

I grow tons of tropicals in containers that I over winter in basements, heated garages, and sunny windows inside the house.

Some hummer favorites I couldn't live without are Russelia equisetiformis and hybrids like St. Elmo's Fire, Salvia 'Amistad', and porterweeds (stachytarpheta mutabilis, Stachytarpheta mutabilis var. violacea, Stachytarpheta frantzii, Stachytarpheta 'Nectarwand Red').

I went crazy this year with the amount of porterweeds in the backyard both in pots and in the ground and this has been the most amount of hummingbirds we've ever had!

We have a garden that always has birds, butterflies, squirrels. We have birds from humming birds to a couple of types of hawks. Usually about a half a dozen some times more and some times less. We also usually have at least 2 or 3 swallowtail butterflies but have had many of the smaller one and some monarchs.

In the garden we have Miss Huff Lantania, butterfly bush, butterfly weed, azeleas, and forsythia, etc. There are many plants you can grow for butterflies. To further attract butterflies and birds we have a bird bath and both a humming bird feeder and a normal bird feeder.

In my mind it would be perfect outside of a window in a small yard as you describe, as there is always color and activity.