I will surely rank Deng more than Mao though
I think without Mao, China can be still developed too.
We can see it in Singapore, Taiwan, South Korea, Japan and many overseas Chinese worldwide.
What Deng Xiaoping did is liberating Chinese people to advance and get rich.
While what Mao Zedong did is by restricting it down to the poverty and backward, because he believe that Chinese people is not white people, that is why Chinese people can't advanced without his help.
BTW, liberating Chinese people is not hard to do...
But what Mao and Deng greatest achievement is a good governance, a good working culture in the Chinese government. Because at first, they disbelieve Chinese people is that great, so they work hard to build a good government structure, to help the people.
But it turn out, Chinese people is also great.
Good government + great people = big bang!