I hope someone can help and I apologise for it being long winded

We live in Manchester and over the past 2 years have renovated our front garden (terraced house )in a victorian style with tiles and rope edging.We have planted the garden with roses,euphorbias,laurel,fotinia red rodin,hebes and hydrangea.
All looking very good.

Now I have built 2 x10 ft length x 20 inches width planters in the back garden, these planters face west/south west, they get the sun pretty much all day except from maybe 2pm till 4 pm this is due to the house casting shade.
I am looking to plant the planters up with evergreen flowering shrubs.I am looking for low growing shrubs growing up to maybe 1 to 1.5 max metres high at the back of the planter and maybe 50 cm at the front.

I have been looking at the following for evergreen shrubs so that they look ok all year round

Heucherella
Berberis thunbergii
Daphne
Heavenly bamboo
Choisiya ternata
Hebe caladonia
Euphorbia
Euonymus
Hypericum
Silver bush

Would these shrubs be suitable? or can you suggest others

I would also like to plant some perenials which would compliment the above shrubs but have no clue as to which ones.

I would like the 2 planters to match symetrically if thats a good idea?

If anyone has a design or planting scheme I could use so the planters will look good I would be very grateful.

thanks in advance

Bill