Some preemptive advice if you're in the market of integrating TTS for some customer or service:
Do not ever use any "humanisation" tweaks. Having a computer voice stumble on a word or fucking cough is uncanny valley and how to make people feel manipulated in one simple trick.
Just don't. Everybody hates it.
Biological programming goes a long way.
It goes hand in paw with being instinctively scared of things that can potentially kill you and other species evolution with patterns and markings that make them less likely to become a succulent meal, Chinese or not.