I was trying to say what Jeff Head said. Thanks Jeff Head!
But challenges remain, in that wanting to keep a fully modular ship makes changing modules difficult and puts your port facilities at even greater risk, and the LCS's speed is also not worth the cost and engineering difficulties either. And trying to fit all that, along with an 8 cell VLS, small PAR, along with the redesign and reinforcement work needed into a ship of only 3500 tons will be quite difficult as well. I can't see it being smaller than a 054A, especially if it's meant to hold multiple types of modules at once.
If you want your ship to have VLS, SAM, and phased array radar, then you may as well go for a real sized frigate instead.
If you don't want your ship to have VLS, SAM, and PAR, then your ship can be smaller, yes, but your ship will also be inherently vulnerable to medium tier opponents and be unable to operate alone or in small groups without overwatch by larger DDGs or FFGs.
But let's pretend that the PLAN does decide to pursue such a ship. A 3500-4000 ton ship with 8 VLS, able to hold modules, with small PAR. You say that you want to build a decently large number for longer endurance patrols in westpac. Okay.
But to build enough of them for this role, will eat up a lot of shipbuilding space and budget that the PLAN needs for their frigates.
See, the difference between an up armed LCS like ship and a true frigate, is that a frigate will be able to contribute more to a taskforce's air defence. It has more firepower, more advanced radar, and more command/control. It is able to survive low-medium threats alone or in small groups, and do things from chase pirates to patrol westpac during times of high tension.
An up armed LCS will have far less to contribute in a CSG or ESG, with only bare minimum self defence capability, slightly more than ciws. I wouldn't be confident sending them alone or in small groups around westpac, where they could come up across an aegis destroyer or more, or could be spotted by a flight of super hornets armed with SLAM-ERs. They likely won't have the ability to do multiple simultaneous anti air engagements at once due to less sophisticated radar, and with shorter range so they'll see any ships or aircraft closer in as well.
If you really want the PLAN to patrol the western pacific during times of high tension and let your ships survive, then what you want is frigates. Enough SAMs to defend against a persistent air attack, with radar powerful enough to see aircraft and incoming missiles at good range and the ability to vector multiple SAMs at multiple targets at once. Enough AShM firepower to ward off or give a good fight against a destroyer or an enemy SAG if operating in a group.
At this stage we are basically talking about fleet structure.
I think the PLAN would be fine with a fleet of destroyers, frigates and corvettes.
055s, 052C/Ds, and 054As/054Bs, and 056/A/Xs. Frigates can contribute to a taskforce, and they can also defend themselves and other 056s during patrols of westpac during wartime.
If you want the PLAN to pursue an up armed LCS, then you'll probably have to bite into the budget of corvette production, or frigate production but more likely both. You'll end up with a large number of ships with minimal air defence capability (more than a ciws but less than a frigate), and only able to contribute ASW to a taskforce, and less survivable in a group than a group of frigates or even a single frigate with multiple 056s I hazard.
I'd prefer a large flexible fleet of true, 4000-5000 ton frigates rather than a smaller number of such frigates but a larger number of up 8 cell, small radar, 3500 ton LCS.
The USN might be able to afford to buy a large number of underarmed LCS -- that's because they have a massive number of Aegis destroyers and cruisers to provide all the firepower. But the PLAN currently and likely will still rely on frigates to provide a medium-high end air defence capability with respectable firepower, to round off their overall fleet. Frigates for the PLAN still provide a respectably large percentage of firepower and capability to the overall fleet, because they don't have as many destroyers as the USN.
If you really want the PLAN to go for a large number of up armed LCS, then you are better off not building frigates and only building destroyers, up armed LCS, and corvettes. Personally such a fleet seems to top heavy for me. The armament and capability gap between the destroyers and up armed LCS is too big, it means there are some missions where LCS is not enough in, but where a destroyer is too much in. However if you want to build a large number of LCS then you'll have to sacrifice frigate production, which would fit the gap between a destroyer and a corvette. See the dilemma? Building only a handful of frigates won't really solve anything either, because there won't be enough of them to go around to be really effective, and a small production run means higher individual unit cost, meaning you're probably better off mass producing more 052Ds or 055s instead.
I think the PLAN should not copy the USN surface combatant fleet structure and seek a more balanced navy instead.
