The C++/CLI wrapper approach does have many advantages. This does make a simple way to use all of the WCF tooling, with any transport mechanism, from within C++. However, it does introduce a dependency on the CLR, which may or may not be acceptable.
Another option would be to use the C++ REST API (aka Casablanca) to call the WCF service directly, using a pure native API. This would require exposing the WCF service via REST.