I suppose nothing making things worse is a strange way of trying to say you want to make them better. Like a young boy harming a young girl he likes because he's afraid to tell her. China knows its actions are damaging its international reputation, creating the very containment trap its trying to avoid and telegraphed or not, and they certainly were with this discussion going on for a few months, China took the right steps in dealing with the US. It shows to the US at least that China can be responsible... for now anyway.
As for the rest of the SCS, I suppose
@Nihonjin1051 has it right as it stands today. China can't unless it changes its stance on the SCS and acts in accordance with international law. Their military build up is fine if they don't use it, their economic hegemony is good if they help their neighbors develop, having another policical voice to rationalize with the US is a boon too. Wielding these powers as weapons, that's what has got China in trouble.
I don't have an answer, odd because that's my job as a risk analyst (no answer on short notice anyway), no definitive or concrete steps taken by China today could undo all the damage and distrust that has been sown into its neighbors.
I concur. While their economic interests align, considering Russia problems with Europe right now, and their political dealings help diversify the region away from US interests and influence, Russia still competes with China for resources, economic interests, military concerns and political power in Eurasia. Friends today don't make friends forever.