You're in USDA Zone 8, near where I live. If you could indicate where in the planting the new shrubs are to go, what color and timing of flowering, leaf texture desired (big leaves = coarse texture, medium leaves medium texture and so on), light exposure, soil conditions...then it will become possible to make some suggestions that may be of use to you.

Sorry I wasn't specific enough. I don't mind that much when the shrub would bloom, spring or summer and medium size leaves I guess. I would like the shrubs to be in the center of the bed, between the trees, since it's visible from the curb and inside the house. It's mostly sun there, and the soil I would say is a bit on the clay side, although we've amended it quite a bit with compost over the years. Would a type of pieris look good mixed in with perinnials? That's my biggest question,what looks good mixed in with peonies, delphiniums, roses and those sort of flowers.
Thanks.

Pieris would look great, but be careful of how much sun they get, they don't like reflected sun bouncing off walls and pavement. Clay in the soil will help them not dry out too fast.

Dwarf abelias are evergreen most years, bloom late summer and fall, and take full sun and can go all summer without water once established. Make sure you get dwarf as the standard Abelia grandiflora gets very large, and pruning them ruins the shape.

Lavenders are commonly used but don't much like clay soil in our wet climate. They would need excellent drainage.

Heathers are great. Most are low growing, but some are more like a shrub. Some bloom late winter and spring, others bloom late summer. Full sun, needle-like leaves.

Kalmias take more sun and less water than azaleas and rhodies, but still not hot reflected sun.

I really like the different textures and shades of green that you get with dwarf conifers, mixed in with peonies and roses.

Old fashioned deciduous shrubs such as deutzia and lilac make the best backdrop for the flowers you have listed. Maybe flank the flowers with a few of these, then have some fine-textured evergreens like yew, holly or box between those and the sidewalk. If you don't have room for the flowering shrubs then the flowers might stand out well against the evergreens, especially if while or otherwise lightly colored. The only drawback with such a grouping is the stark contrast between the solidity of the evergreens and the lightness of the perennials. With deciduous shrubs between the two types you have a transition.

Thank you for your suggestions! I like the idea of a deciduous shrub or two mixed in as well. I do have a hydrangea there already.

Bigleaf hydrangea is good with hardy fuchsia. Hardy fuchsia goes well with abelia. Abelia likes a warm and sunny spot (hardy fuchsia does not need shade in this climate).