Zhao would have had to play his hand very carefully to impose his views of political reforms alongside economic ones, as the Chinese leadership was concerned that such a policy would lead to the same results as in the USSR, namely systemic collapse. This is the reason they freaked out when the student demonstrations of 1989 took place, and why they overreacted. Having the protests peter out would help Zhao avoid being sidelined by the supporters of continued authoritarianism, but the following couple of years would be very difficult for him, between simmering popular discontent and calls for a tougher line from Deng Xiaoping and Li Peng.
Assuming he makes it through that troubled period, in the rest of the 1990s he might be able to gradually loosen up the regime's dictatorial aspects, following precedents set by South Korea and Taiwan in the previous decade. However, two problems China has that neither country had is its size and its diversity. Reforms decided by the central government have to face a lot of inertia at the level of local implementation, so authoritarian practices would have lingered for some time in the middle and lower strata of the state apparatus. Also, Zhao would have had to make sure that political reform wouldn't be interpreted by China's more restless minorities as a green light for attempts at secession, and this may have required a symbolic crackdown, probably on the Uighurs or the Tibetans.