I was thinking Annabelle hydrangea, but not sure how these would fare in full sun, and how that would look being the same height as the sandcherry. Ideally, what I'm trying to do is create a private alcove in the area alongside the garage.

I'm limited in my knowledge of shrubs. I saw Chardonnay Pearls in my B.P. catalog, caught my eye since it is supposed to have lime yellow foliage, and the spring flowers are a plus.

I like a clean somewhat formal look, so a shrub open and airy wouldn't work for me. I previously had Neon spirea in this area, didn't care for them.

I was also looking at the Sawara False Cypress - Vintage Gold, but of course the magazine photo looks spectacular, but all other photos I've seen are more irregular forms, and not sure I'd get the height I'm looking for.

Feedback on the Deutzia? Any other suggestions? A height of maybe 3 feet max would be ideal, and I think this would be considered a border planting?

Clethra Alnifolia, Sixteen Candles? I thought the spikey summer flowers would be a nice contrast with the purple leaf sandcherry. Or, Ruby Spice with pink flowers.

Including shearing to resemble boulders. The Sawara cultivar you mentioned can certainly be pruned to assume the appearance you desire.