Our office did something like this a few years back (I wasn't involve with the design only the construction support). The project was a riverfront part and parts of the seawall were sheets with cast-in-place concrete facing.
The concrete was held in place with shear studs. As far as accounting for the weight of your facing, why not treat it as a lateral load? Multiply the eccentricity by the weight of the concrete and add that moment to the moment resulting from soil pressure.
About 20 years ago I was resident engineer on a bridge fender project. The design called for twelve 35' diameter stone filled sheet pile cofferdams. The exterior of each cofferdam was covered with timber. The design called for threaded rods welded to the sheets to hold the timber. However, the contractor shop welded nuts to the sheets and then bolted the timber on. It worked out well because field welding would have been difficult since the specs called for shop coating the sheets.
