Crown of thorns (euphorbia millii) would work. Zigzag plant (pedilanthus tithymaloides), a succulent, would also do nicely.

I've had luck with geraniums, snapdragons, and a yellow creeping, small flowered plant (lost the tag). My pots are outside the entry and get blasted all afternoon with hot sun.

I actually had the geraniums survive the year and started blooming this year. I do pack my plants in and cover the potting mix with a thick layer of wood chips. Fertilize with time-release and water every day. I'll try to take a pic of my pots tomorrow.

So far, so good!

Jane

Desert rose is very showy when in bloom and like dry conditions.

What works great for me in front door pots, intense Texas full sun, and reflective brick/stone heat (but regular, sometimes daily, watering):

Bougainvillea, Mandevilla, Cordyline, ornamental grasses, Pentas, Portulaca, Rosemary, Potato Vines, Crossandra, Marigolds, Blue Daze, Globe amaranth, various Salvia varieties, Perilla ‘Magilla’, Zinnias, Sunpatiens, Verbena, Ixora, Gold Star Esperanza, Croton. I’ll add more as I think of them. :)

Of that list, if you want non-stop blooms, least messy, won’t get scraggly and tired in late summer — Mandevilla, Pentas, Bougainvillea, Crossandra.

All of these, except salvia and rosemary, are annuals for me ... the tropicals may not be annuals for you ... so I don’t know about winter care. For my container plants that do come back, I usually plant them in a bed after the first container year. For my front door area specifically, I prefer to start over fresh every year.

The sun coleus are great for giving you lots of color in the summer with very little care other than watering and occasional fertilizer. I just made a mixed container with a cranberry hibiscus, lime green ornamental sweet potato, vincas, marigolds, sun coleus and "Little Ruby" alternanthera. It's loving the sun so far.