Bricked Flower Box (on top of Pavers) to add Colour, Sun Protection and Privacy to the Front Yard

[Greg_W]

We've toyed with putting pots and plantar boxes along the inside of the front wall but now we have come up with a new idea.

Laying a row of brick or block inside the line of the existing wall (making the inside wall the same height as the existing wall - noting there is a step on the pavers already)

Rendering the brick or block the same colour as the existing wall (or getting the whole wall re-rendered)

Adding a waterproof membrane to the inside of the walls (and the paving floor). 

Drainage - there is no access to the storm water pipes so I'm thinking of having an Ag line going contra to the natural slope of the pavers (away and to the gate) and then having a weep hole to discharge the excess water trickle to the front path (away from the gate)

We were then thinking of a colourful ground cover (good afternoon sun facing due West) as well as higher plants like Ficus hillii "Emerald" to help shade the courtyard in summer and add a little privacy.

Anyone out there with something to add that we haven't thought of? Ideas? Improvements? A better way?