both Hass and Cambrige are crazy about GPA, so if your GPA is 3.0, better neglect the two;
For Ivey, if you wrote good essay and spoke fluently, you have chance.
My two cents
no problem in spoken English. I will pay a pro for writing the essay, so not a big problem.
But would you please kindly tell me how much GPA they are looking for?
For Cambrige, two special requirement, GPA: >3.3; TWE:>5.0;
For Hass, I am not sure.
Last but not least, it is definitely not bad to have a pro for writing essays, but you yourself should dig into yourself deeply first. The deeper, the better.
Your background is good. cambridge and ivey's application is not difficult, but berkeley is quite difficult for chinese, especially for you from mainland!