I think the LPD is much more capable than the LSTs, and even with two heavy lift helos operating at once on the deck, I believe the hangar spaces my be able to hold two large and two medium...but am not sure on that. Anyhow, with two at a time, and with a couple of the Type 071s involved together, that means four heavy lift helos coming at you at once for air assault, while probably six full LCACs are coming at the beach at the same time.
That's a lot to counter given that it can land on any beach, anywhere as long as they are suitably supported.
With the PLAN LCAC capability and the air assault capanility, if two LPDs act together, they can pull off a pretty good landing, but would have to have additional air support, either from the carrier or land based.
But these LPDs are just a first step in the upgrade to the PLANs amphibious assault capability. My guess is that ultimately the PLAN will have maybe four LHDs and maybe six LPDs that will be able to, with some of the later model LSTs form up very nice ARGs for the PLAN and be far, far more effective than anything they could otherwise perform with the LSTs alone.
An LHD, with two LPDs and four LSTs, escorted by a couple of FFGs and DDGs would make a potent ARG.