The problem with suggesting five BC's is that if you desire to go with the Backplate and Wings concept, there are not that many shops that offer them. Why? For various reasons, one of which is that they hope you will buy the "lower" end of the spectrum, and then return to them later to purchase the next step up when you exceed that one, and repeat ad nauseum.
If you want to see, touch, feel, try on backplate/wings concept, try to find dive shops that carry one or more of the following brands: OMS, Dive-Rite, and Halcyon. Now, there won't be any specific models within these brands due to their modularity. But being able to look at them might help wrap your mind around what we're talking about.
Does that help some?