Here are some reading metrics based on our experiences that may help you decide the relative pace of Chinese and English instruction for your children.
Comics stage: DD#1 started reading comics at ~ 8-8.5 years of age and DD# 2 started reading comics at 7.
Character only short novels or novels: DD#1 started reading 沈石溪’s animal stories at ten and half (10.5) and was able to advance to reading 金庸 by ~ 12.7 (select novels whose plot she knows already through watching TV, via initial Scaffolding Reading Experience or SRE). DD#2 was able to read Narnia in Chinese at ~ 9.8 years of age and now (~ 11.3) can read Harry Potter book#1 in Chinese (i.e. books that he read in English already) without SRE. Since DD#2’s Chinese has always been about a year to a year and half ahead of DD#1 in terms of reading, I have now slowed down DD#2’s Chinese to focus more on English since I know that she should be able to read 金庸 by 13.
I hope these metrics help you choose the relative pace of instruction for both Chinese and English.