This is me and my mum when there was real access to the docks and seafront (I did grow into those shorts eventually).
The marina at present is hidden away for the very good reason of security, and that need is unlikely to change and probably increase.
The photo does show what appears to be a backdrop of industrial warehouses on top of a sheet piling wall which won't be at all attractive - what is needed is more detailed plans of what is going where and the final appearance.
The developments at Folkestone harbour last autumn which were instantly attractive and successful show what can be done in a similar setting, as does the thriving working harbour at Whitstable. Let's hope we get similar at Dover but I'm not convinced yet.