1) Absolutely agree, the Chinese government after the war was absolutely horrendous. That, however, is only slightly relevant to the question of what to do today.
2) You can always use the excuse "I don't want a billion people that I care about to go through the hell that is Syria."
3) I don't rule out that possibility at all. I'm just saying the risk that it won't work seems too high given how bad the outcome would be if it doesn't work.
Of course it's possible. And much better examples of that are post war Japan and Germany. The changes there literally made them global leaders.
I'm not saying it's impossible. I'm saying it's risky, especially for China which hasn't had a history of being successful without an authoritarian government. And which had a terrible history of chaos when it didn't have a strong government.
2) You can always use the excuse "I don't want a billion people that I care about to go through the hell that is Syria."
3) I don't rule out that possibility at all. I'm just saying the risk that it won't work seems too high given how bad the outcome would be if it doesn't work.