Please help! need some ideas for planting in my front garden

This is a blank canvas and would like to have some structure in this bed by my front door. initially I thought some dwarf conifers would be nice so bought a few to plant. After more research I found there growth would be far to much also I didn't think about roots and foundations!!. So I'm now stuck and thinking some nice interesting shrubs could be used instead? Id like low maintenance, but interesting all year round, looking for ideas please. Garden is south facing, exposed, soil I think is well drained possibly loamy as it is good topsoil and mixed in with some compost for the top 2 foot then shingle on top of heavy clay. I would like to put in a cistus x purpureus and maybe something tall at the back? not sure on what would work well together?

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