The case you're mentioning is well understood by the Honk Kong citizens, and your suggestions has already been addressed. In fact, the extradition to China was at first only allowed if the crime required 2 years of jail time in Honk Kong to make a case, then after the protests it got pushed to 7 years. But watch this YT video, as the HK citizens tell you why this is still a bad idea: https://www.youtube.com/watch?v=z0i9yVphOZ8

ps: i'm not telling you why because #1) I won't do it justice and #2) it's worth watching the whole YT video.