Honestly I think you need a Guangxu emperor whose much less in thrall to Kang and gives him and his cronies less political power, while maintaining some level of contact. It was this cronyism and fear that Kang was using "reform" as simply a way of gaining personal power that made Cixi incredibly intolerant of the reforms, when it had usually been her heading the reformist elements in decades previous.
Alternatively one thing that could help is reducing Japanese ability to interfere in China and lessen the fear that Kangs reforms would make China a Japanese tributary.