The best way for Chinese reunification is wage an economic and PR war and wait patiently. The goal is to make China a better place to live instead of Taiwan for young people (not the raisins) and you'll start to see them leaving the island for the mainland for a better future.
An attack on Taiwan will draw the Americans into the fight simply because they love killing people (I truly believe that). Given with the US economy is in, let them hit rock bottom and China will come out on top without firing a shot. Using the military option will make China look bad forcing other nations against her. It's nice to see China modernizing it's military to ensure it's sovereignty but IMO doesn't have enough military assets and experience to wage a prolonged war. For example, having an AC is really useless unless it's part of a CBG and it takes time to properly operate it and China will need at least a few CBG's. If a military option is unavoidable then employ methods to force the opponent to fire the first shot making them look like the aggressor.
IMO, if Taiwan does, for some reason, declare independence, it's likely an empty threat.