I think there is another case to be made for this new ship potentially being an arsenal ship. Aside from the cost per VLS consideration by AndrewS. Considering the likely combat conditions if a potential war in the near future breaks out, the likelihood of this conflict being close to the home coast is very high, also a larger number of small arsenal ships with one command and control destroyer (52s and 55s) could provide the swarm / over saturation tactic a new level of deadliness.
imagine that we have one destroyer as a command and control along with a few to a dozen of these arsenal ships as a battle group swarming a carrier battle group from multiple directions and splitting both the offensive and defensive assets of the enemy battle group that can be focused on any one direction. Additionally, the lost of any of the small arsenal ship would be much more acceptable than losing a 52 or 55.
Furthermore, rearming has always been an issue of VLS as it take quite some time to rearm, by splitting the concentration of the VLS onto more ships, it allows more tube to be rearm simultaneously at port, it should provide a better up time during war time conditions, assuming missile production can keep up.
Once again, you do not need a 055 or 052D for command and control for a whole bunch of heavy missile corvettes. Which by the way isn't a novel arsenal ship concept. This is the old Soviet missile warship concept through and through. This is exactly what the Tarantuls and Moliniyas do, although they are between the edge of a Corvette or a FAC. These craft can be loaded with as many as eight Sunburns or in a moderned form, 16 Kh-35 Urans.
The idea of missile ships protecting the coast assymetrically against a larger navy is an old one going back to the Soviets. It's only we replaced slant missile launchers to VLS. This idea is still with the Russians today and the PLAN can easily get exposed with these ideas through their exercises with the Russian Far East Fleet which has a number of these ships exactly in mind to do such tasks.
When you are fighting in the home coast, land based command can do, using satellite communications and coordination with aerial fleets.
Z-20 sized helicopter deck still does not discount the possibility that the vessel might be for export as many Navy's still use the Z-20 sized ASW helis like Thailand and Algeria.
The export idea still has a big problem because there are no reported orders from Algeria or Thailand since such orders are done with much publicity and fanfare. The Thai export 071, and the Pakistani Navy ships held very public celebrations when their
keel is laid. Algeria is too poor for more ships besides their 056 type orders and Thailand, guess what, has a pro American government elected.
Such orders would also be accompanied by orders of missiles, which there is none. Such missile orders would be very public and splashed all over the Western defense media.
