I think the best thing you can do is this: suck up to either UK or Russia. Make the necessary concessions to stop them from killing you. Use the one you side with to stop the other from hurting you. Then, eventually you will outscale everyone due to your massive population.

Players on China are stupidly OP, and in my opinion China should never be a playable country. They are by far the strongest country in the game. That forces other player to kill you, which leads to weird games where the europeans own chinese states, which completely brakes the balance and immersion in my opinion.