Well I don't want China to bog itself down in 10-20 locations, of course. I think it should strategically pick one (1) fight for national liberation and support it more fully and openly, e.g. Palestine. The US will of course try to make this as painful as possible for anyone daring to push back on them.

I don't even mean sending troops. Right now, the status quo with China internationally is that the capitalist empire is committing a genocide to keep its keystone to the domination of a subcontinent politically viable and the response of states with whom we are meant to have affinity are politely registering complaints. This is leaving all of the direct work to liberals and neighboring national liberation movements (or those who recently won national liberation). China's contribution, which is massive, is to create the baseline of multipolarity that makes all of that possible. However, China could, for example, begin leading a push to isolate Israel. Outcomes that would substantially undermine empire in Palestine include fully funding UNRWA and doing a full push to sanction or even blockade Israel. China should be getting practice in doing PR on this because they suck at it. Hire Al Jazeera reporters and learn how to craft angles from them. Etc etc.

I think they avoid this because the main good factions are well aware of how weak China was very recently and they understand that their project is overall still fairly fragile. They also see storm clouds in destabilizing the US. I think they have adopted an approach that is so conservative it is actually counterproductive, though.