Mrs A has come up with others that have worked for us over the years.
She would agree with Nichola and Geraniums for all the elements you ask for and there are so many size variants available.
Cycas (Sago Palm) bit expensive but a great show, not keen on full sun in July August.
Bush Bougainvillea will stay small, be sure it is the bush type.
Maybe not easy to come by The ornamental Bush Pomegranate, yes it will show fruit.
Our Bougi and Pome and Cycas in pots are now 10 years old and need little or no maintenance again outside all year.
Last Plant is the Village flower. We buy these each year from the Tuesday Market on the Canal side, turn right over the wooden bridge there is an oldish man that sells them wrapped in newspaper 5/6 in a pack,mixed colour 2TL. They flower all summer and are just beautiful. Only know them as "Village Flowers" Not perennial.