I'm just a Chinese student from the West so take it as just my two cents but I don't think it will evolve to phonetic syllabaries. Chinese has a lot of homophones so it's useful while reading to have an extra semantic meaning. They also say that once you're used to it, you read faster but at my level I can't confirm it. So with modern input devices you're basically simplifying the hard part of the characters, which is writing, and keeping the reading part where they're better than pure phonetic systems.