You can also plant rosemary with lavender. Height of rockrose varies with kind, most sold are not very tall. Most successful is Cistus x hybridus, that make a fairly large and dense mound. But even with this one many plantings have some dying back of branches and gaps in them, as with the lavender and rosemary you need a hot site with quite good drainage.

A classic is roses + lavender (and roses + rosemary), those would give you the color range and long season - maybe with the lavender etc. being present you don't need every shrub included to be evergreen.

bboy, thank you! I love the idea of the rosemary. I had thought of roses, but I wasn't sure if I could pull that off. I think I'm going with the rosemary!

Depending on how harsh the winter is, roses would probably keep some of their foliage year-round, too. Admittedly, overwintered rose leaves look pretty ratty by spring, but hey, at least it's not just bare canes...