The Navy continues to be far more successful in developing missile defense systems that work, largely using existing missiles and upgrades sensors, than the other military services.
The idea of having more than one crew for a single ship, to maximize the time that the ship can be at sea called "Sea Swap" in the U.S. Navy, is working well, being used more widely, and can increase the deployable size of the fleet by a factor of 40%. Historically, a few as a third of Navy ships have been deployed at any given time.
Cyclone class coastal patrol boats (380 ton boats with a crew of 30), are much smaller than the U.S. Navy's 3000 ton Oliver Hazard Perry class frigates (with a crew of 300), which are in the process of being phased out in favor of three times as large destroyers, or any other combat ship in U.S. service. They had previously been so unpopular that the Navy was trying to pawn them off on the Coast Guard, which didn't want them, or to remove them from service entirely. Now, the Navy brass has decided it likes them and is trying to put as many into U.S. service as possible, which has the positive effect of putting more ships into service for a nominal cost compared to new ships.
This shift in attitude is largely a function of a shift away from a cold war mentality of trying to build a "blue sea" Navy, where the ships were viewed as useless against large Soviet warships. The patrol boats have no missiles or torpedoes (except for defense rocket flares to divert incoming missiles), no capacity to carry helicopters, and their largest standard weapons are a pair 25mm (2") cannons, and a 40mm grenade launcher similar to the largest Army small arms. By comparison there is a 3" naval gun on frigates, a 5" naval gun on destroyers and cruisers, and a 6" naval gun on the proposed DD(X) (now the DDG-1000), in addition to guided missiles and torpedoes and helicopters on each of those ships. Thus, the patrol boats are incapable of sinking any warship or large merchant ship, and are helpless against even a small military submarine.
But, now there is a renewed emphasis on "littoral" activity (i.e. coastal tasks) often called a "brown water" navy or a "green water" navy, where the focus is on stopping small attacking speed boats, checking merchant ships for smuggled arms, and taking on pirates, for which the patrol boats are well suited. They are an order of magnitude smaller than the proposed Littoral Combat ship, which will be about 3,000 tons and have a core crew of 75 sailors, which will be used for anti-submarine warfare, mine sweeping, fire support for coastal troops, deploying special forces, and a variety of other missions with task specific modules that can be switched out in a day or two.