Goodness....so many ideas! For starters, how about a lovely Cistus. They are almost fully evergreen, love sun and flower beautifully over a long priod. Cistus creticus is one of the best, and cistus pulverulentus. Don’t get too big..only 3feet, nice rounded habit. Silvery sheen to the foliage. Then there’s Ceanothus. Gorgeous blue flowers, small green leaves. Loads of varieties. You’ll get loads of ideas by just googling ‘shrubs for hot sunny border’. Herbs also do really well, with the added bonus of aromatic foliage. Rosemary for all year interest, lavender, thyme...any of the mediterranean herbs.

It depends on how tall you are prepared to let it grow but a small shrub is Ceratostigma, the hardy plumbago with its pretty pale blue flowers.
Another, taller one, is choisya, the Mexican orange blossom which is fairly neat and well rounded and with a beautiful scent. I particularly like Aztec variety.
Then there's the tried and tested Rosemary which will provide you with fresh sprigs for cooking.
I have two Physocarpus bushes. One has lime green leaves and the other has deep red ones. I cut both back in the spring.
There are many more though. Good luck.