You are making these complex and resource and competency intensive operations sound like they are easily achievable, and that once they succeed at the operation then it will be game over.
But attaining those operations in the first place is far from easy, and instead of thinking about what the PLA can do after they've succeeded, we should be thinking about what they need to organize and procure to achieve those operations to begin with.
Re-read your post and see the number of times you've written "if China just does xyz". And think about how difficult it is to actually do those things.
Like I said they are just hypotheticals and ideas. I don't actually think this will happen and I don't want it to happen either.
In reality the best thing china can do would be to up it's information and media game, and meddle in Taiwanese domestic politics, overthrow hostile govs and install pro china govs. Of course that would make china hypocritical and against it's non intererence foreign policy but it can also be argued that Taiwan is not sovereign country and is part of china and unended civil war so it's fair game.
Stop saying things like flattening the whole island. PLA is not going to do that. We are having this whole discussion because the best way for them to take over Taiwan is a quick campaign that causes local to give up and surrender without causing large amount of casualties. You don't want rest of the world charging China with war crimes.
You are expecting best case scenario where I'm expecting worse case scenario. I'm looking to save as many lives and equipment of chinese military as possible. A light/quick campaign only works if they surrender. If they don't, then what? I'd rather not drag things out and give time for the world to get involved.
Even if china flattens Taiwan, it will be under the scenario I mentioned with all innocents given chance to leave to safe zones, so anyone remaining is fair game. Afterwards the money china saves in lives, sanctions and equipment losses can be used to rebuild Taiwans lost infrastructure. It won't take long at all with full power and resources that china has. That will be the easiest and cleanest way.
Also, china would not resort to force unless there is no other option. I'm of the mindset that you don't fight unless you're 100% committed. Even in a street fight. You don't fight expecting things to be easy and the enemy to not be trying to kill you, and you holding back from seriously hurting them and refraining from "dirty moves" etc. They could pull out a knife and just shank you after.
You don't fight a war and do it half assed hoping your enemy will surrender instantly. Otherwise you might as well just do blockade and not even go in and have zero casualties. But that will drag it out and china will probably take more damage from world co ordinating sanctions like they are doing agaisnt Russia.
Or better yet not fight at all, which is china's current position. But if forced, I suggest go 100% straight in hard and fast, no half assed shit. Imo if there was chance of quick surrender or whatever china would not even attack in the first place and just negotiate.
Charging china with war crimes? China just needs to ignore it like usa. Sanction their families and relatives like usa. ICC is a joke.