Abuse. Abuse. You are worried about abuse? How about the occupation of Hong Kong, the attempt to extend occupation, and then, upon determining that the occupation could not be extended, doing everything in your power to create strife, division, conditions for counter-revolution and secessionary movements, and maintaining as much political and economic influence over the territory as possible?

Do you think that might be open to abuse? How would you solve that problem? What sorts of solutions exist in the imperial world for resolving this sort of problem?

What you don't seem to grasp is that One Country, Two Systems entails One National Defense. Collaboration with Western imperialists who have subjugated China for centuries is going to be handled by the One Country, not the Two Systems. Unlike the imperial holdings of the West, however, Hong Kong is actually democratically integrated into China. Ask Puerto Rico, Guam, the Virgin Islands, etc how democracy is working out for them?

You also aren't actually analyzing the bureaucratic workings of China's legal system and aren't steeped in their history, traditions, and precedent. You are reading a Western spin on what's actually happening. You can't read Chinese, so you can't read Chinese law. You can't actually engage with Chinese events at the same level of detail and analysis that you can of English, American, Canadian, and Australian events. So, forgive me if I don't find your arguments compelling, since they amount to accusing Xi of being an autocrat in what is demonstrably a democratic institution operating a rules-based bureaucratic system that has a decade-long 95% national approval while simultaneously operating the most complex multi-ethnic country in the history of the world including autonomous regions wherein ethnic nations experience a greater degree of cultural self-expression and self-governance than anything the West has ever produced. Clearly, if China worked the way you think it does Xi would be calling all the shots and people would be discontent and the governing of 1.4 billion people of 57 ethnicities would be coming apart at the seams. Instead we see that it is France, UK, and USA that is falling apart dealing with far fewer people and with far less ethnic diversity and with far less ethnic autonomy. Something in your analysis is fundamentally flawed.

Back to your point about abuse, though, should you be worried about abuse of power in China? Is that where your energy should be going? Does China operate 600 military bases globally? Does China operate extrajudicial torture chambers all over the world? Does China launch new wars of aggression every few years? Does China deploy chemical and nuclear weapons that continue to kill thousands of babies the world over for decades? Does China suppress language and culture of people living in its borders in a continuously unbroken 600-year genocide?

As far as I can tell, all systems have corruption, all systems have abuse of power - it's the essence of governing systems that they are this way. What we should be worried about is actual abuses, not potential abuses. Worrying about potential abuses allows you to focus on China while the USA kills millions, tortures with impunity, trains terrorists and death squads, and sows death and destruction everywhere it goes. Focus on the problem. China's not the problem.