1. I think there's little doubt that once a 052D or 055 is underway in high alert there will be very little chance of a drone getting through. But when engagements drag on for months it will no longer be feasible to lob a HQ-9 toward every little Shahed coming their way. So I think the argument for the 555 missile has gotten a lot stronger.
Argument for 555 predates drones; HQ-9 is a large and not very accurate down low missile (this is a big reason the warhead is so big) with very big Dmin. Traditional sea skimmers alone justify 555.
The argument now goes that much more is necessary. Good first step is probably a guided 130mm round, but at very least, additional RCWS to cover blind angles are necessary.
2. For CIWS, the current 1130 in the front and HQ-10 at the back configuration still feels like it's likely sufficient, but I think there's also a chance they try to beef it up somehow.
The main problem is the optimization point. CIWS tries to throw out as much ammo as possible, while keeping the mount without unnecessary weight up (inertia problem). I.e. it's built for high-rate automatic fire, but doesn't have all that much ammo.
Furthermore, specific installation limits angles dead ahead.
3. I think we've seen quite a few cases of ships in port or not in full readiness getting hit because weapons were not ready. Since it's impossible for a a ship to be perpetually running its weapons systems at high alert, maybe a RCWS located at the sides of the ship with its own independent TV/IR tracking would be useful as a last line of defence even if CIWS or radars are not activated. Reaction time and ability to react would improve significantly if something like Corsair USV gets through undetected
Yes, absolutely. Moreover, ideally, they should have the capability to be independently powered, even if ship lights went down for one reason or another.