Can you give us a bit more detail about the height you desire, the type of soil you have and what part of the country you live in. Some of the cinereums such as 'Lawrence Flatman' or 'Ballerina' are light pink but they are small plants more suited for a rockery. Several of the oxonianums like 'Claridge Druce' are a brighter, deeper pink, but they are taller, with a more open structure, and need a moderately moist soil. The boxwood hedge will suck a lot of moisture out of the soil so anything you plant next to it will have to be extra drought tolerant and tough. I have perennial candytuft (Iberis sempervirens) next to mine and it does quite well, The iberis can be pruned back after flowering in the spring to make it more tidy and dense. It is white of course and not pink.

Here is a link that might be useful: Iberis 'Snowflake'

I need something around 12" high as right now I grow impatiens there and they are really too short to show. At one end of this spot I have purple huchera and the other end I have fire and ice hosta. One of the problems with the spot is that one end gets more sunlight than the other. Because this is a long spot I was interest in the Windscombe because it has both light and darker pink at the same time (color changes as flowers fade)or jolly bee. I don't want anything too dark as it might not show up. I don't mind sprawly geraniums. I grow rozanne and find it easy to keep in check with a few snips. Any thoughts? Thanks