For those who might be interested, here is a “pdf” with a bit of information on how the Navy is implementing their mission module concept on the Littoral Combat Ship (LCS). Unfortunately the information only covers the 30 mm gun and 60 round missile system. They are also developing mission modules for ASW and Mine Warfare.
I like the concept for the Coast Guard, in that it provides a way for Cutters to be designed to be armed for wartime missions without the service bearing the cost of maintenance, training, and personnel in peacetime. It might be applicable to the Offshore Patrol Cutter (OPC) and possibly other cutters, such as future icebreakers and arctic patrol cutters.
There have been some difficulties with the surface to surface missile (SSM) system being developed for the LCS, the non-line-of-sight launch system (NLOS-LS), which began as an Army project, but which has now been taken over by the Navy. There is a relative recent summary of the status of the project here. It does seem the Navy is going to develop something to fill this perceived need, as well as the existing hole in the decks of the LCSs. There is some additional pictures and information here. If the Navy does get NLOS-LS working, it may also be useful on much smaller vessels. Looks like a 15 round launcher might fit on the FRC.