PLA VLS can't be that much bigger to make a significant difference in war. Quantity can beat quality.052D does seem a little light on VLS compared to many other modern destroyer classes like Zumwalt (80), Sejong the Great (128 or 88), Maya/Atago/Kongo (96/96/90), etc. However PLA VLS is larger and it's not like 64 is majorly inadequate plus 052D has HHQ-10 which most of those do not (they're retrofitting Burkes with an 11 cell launcher for the US equivalent apparently) and so some of those VLS will probably be quad packed RIM-162s which are essentially baseline on 052D.
Yes, more radar and CIWS on more hulls will help even though the overall number of missiles is the same.It could be the case that in a high intensity war having 6 destroyers with 60 VLS is better than 4 destroyers with 90 VLS even though both sets of destroyers have 360 total VLS. It's hard to know but maybe more network nodes and sensors to distribute over a larger area is better as long as those destroyers have at least a reasonable number of VLS.
Reloading VLS is inconvenient, but the PLAN should be able to do it easier since they're close.Also there's geographical considerations where for USN which more frequently operates far from their home bases might prefer less warships with more VLS each. PLAN might focus their mission closer to home and not be too concerned about deploying to the other side of the Pacific so might prefer more warships with less VLS each.
Chinese UVLS is significantly larger than MK-41 (0.85m diameter vs 0.635m) or 80% larger area/volume wisePLA VLS can't be that much bigger to make a significant difference in war. Quantity can beat quality.
Yes, more radar and CIWS on more hulls will help even though the overall number of missiles is the same.
Reloading VLS is inconvenient, but the PLAN should be able to do it easier since they're close.