British Columbia: Need to pick a spreading plant to cover new retaining wall

A local Contractor will be replacing an old stacked rock wall at the bottom of a slope with a two tier wall of "large" boulders on Bowen Island.

The old wall had spreading juniper flowing over it like a green wave and a standing juniper hedge, which were both removed unfortunately.

I liked the look of the mature spreading junipers, and will likely replant with them, but while they grow I'd like to have something else inter-planted that will compliment the junipers and spread quickly. The variety of juniper was unknown, and the spreading were resistant to pests much more than the standing.

Final grade has not been determined but the new wall(s) will split a total elevation of 2+m on one end and 3+m on the other, running around 14m long. Northwest facing, afternoon sun.

Suggestions on what species of juniper and other cover should we use?