Well actually 054/A is no way remarkably more heavier or larger than any counterpory frigates. It is big frigate, well over 3,000 tons displacement, but those 4,000-5,000 ton numbers are hugely over-estimations. Lenghtwisely the ships are about 125-130 meters which alse correspond other frigates around the world.
My somewhat stubborn yet edjucated quess/assumption/analyze has been that the main reason for chinese DDG development being what it is is the proplems and/or delays to provide proper gasturbine propulsion for the destroyers. The overall development of PLAN surface fleet during the late 90's and whole this decade speaks in favour of that intruperation and 054A is aligned to it. Where as othervice the 054A is near the levels of corresponding modern frigates around the world, it's propulsion solution, diesels is more paralel to seccond-rate patrol frigates in west. Chinese knows how to make marine diesels and thus the need for modern surface combatants is fullfilled with design which can be produced in larger numbers but still being othervice up-to-date in its capabilities.
Ofcourse the DDG development delay has other factors as well aside the propulsion arragments, but IMO that is the biggest single factor in it.
Sumdud and me were talking about this the other day about whether PLAN has a any good COGAD, CODOG, or COGAG. We haven't heard anything about them.
Some how PLA likes the 054A more than the 052B or the 052C by building more ships. Even though it's a fairly big frigate like Corbato says it is still smaller compare to the destroyers the other navy in Asia has. Korea, Japan and Russia all have ships much bigger and maybe even the Indians. I have read articles that said China has the lowest average weight of ships comparing to the other major navies. I think the reason causing this is that China's majority of surface ships are made up of older frigates built earlier in the last century, so by building the more modern 054A frigate will help towards solving this problem.
If you look at it developed before the 051B would be classified as a "frigate" due to their displacement. Even the 52B and 52C are pushing it to be a destroyer when other destoryers like the Typer 45, Kongo, KDX-III, Atago, and Burkes weigh 8000+ plus when fully loaded, while the 52B and 52C are around the 6,000-6,500 range. While he Álvaro de Bazán class frigate of Spain weighs 6,250 when fully loaded.